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serpent615
2007-12-30, 08:10 PM
I’ve seen these before, but it's been a while, so I wanted to bring back an old favorite...

What are some of the best uses for an Immovable Rod you guys have seen?

I just had a character have his returned to him (long story, essentially they were inside of him, but I was reincarnated with a new body), and want to do something cool with them.

tahu88810
2007-12-30, 08:20 PM
You could use it to climb up really high, cast featherfall, then jump down on an enemy and pin them (the opponent) beneath your sword...or something...
Just a thought...

Xefas
2007-12-30, 08:20 PM
I think my favorite use that I've heard of was a Lich taking his phylactery, blindfolding himself, flying to a random location in a random portion of the sky, and setting it amidst a bunch of Immovable Rods set into a box shape. Then, he'd cast a Permanency-Invisibility combo on all of them (and the Phylactery) and finally Permanency-Magic Aura on all of them and the Phylactery to make them undetectable.

[Insert Neat Username Here]
2007-12-30, 08:21 PM
Surgically implanting it in somebody could be interesting . . .

introducing the immovable leg.

Jannex
2007-12-30, 08:22 PM
I had an amusing use for an Immovable Rod in the campaign I was playing in this past semester. I was playing a rogue with Martial Study: Shadow Jaunt. In the penultimate battle of the campaign, the BBEG started flying up, hovering about thirty feet above the ground. I downed a potion of Greater Invisibility, pulled out my Immovable Rod, and used Shadow Jaunt to teleport up and behind the BBEG, activating the Rod to keep me in the air. I had a high enough Tumble check that I could easily have soaked the fall after the fight. So I was hanging invisibly in the air right behind the bad guy, ready to sneak attack the living crap out of him on my next turn.

...If the party psion hadn't one-shotted him before I get my next action. Because psionics are "balanced." :smallconfused:

Xefas
2007-12-30, 08:28 PM
...If the party psion hadn't one-shotted him before I get my next action. Because psionics are "balanced." :smallconfused:

If it makes you feel any better, if he'd have been a wizard, you probably wouldn't have gotten the opportunity to take your first action.

Kurald Galain
2007-12-30, 08:40 PM
Naming it Employee of the Month.

Solo
2007-12-30, 08:41 PM
Swapping it with the Paladin's wooden stick.

Use latex gloves and wash your hands afterwards.

Freelance Henchman
2007-12-30, 08:42 PM
Naming it Employee of the Month.

In Rod We Trust.

The Faceless
2007-12-30, 08:46 PM
Enabling X-men references. "Nothing moves The Rod!"

Enabling crude innuendo (Though not as much as the rod of lordly might)

Destroying ships (Activate one in the path of a galleon and watch as it punches a hole through the hull from bow to stern)

Slowing falls

Doing those flips and loops on bars that The Prince of Persia does, only now you bring your own bar with you, allowing infinite uses of it

Handy hammock suspension

SilverClawShift
2007-12-30, 08:57 PM
We had a party member cross a huge canyon by going "hand over hand" with two immovable rods. He had a chain attached to his waist, secured it at the other end, and the rest of us just crawled across the chain.

Reel On, Love
2007-12-30, 09:12 PM
...If the party psion hadn't one-shotted him before I get my next action. Because psionics are "balanced." :smallconfused:

What makes you say they aren't? Either the BBEG failed a save (spellcasters can force saves, too--and they're better at it) or got killed by damage (in that case, the DM made a BBEG with irresponsibly few hit points--and both spellcasters and melee characters can do lots of damage).

Enlong
2007-12-31, 12:41 AM
;3728241']Surgically implanting it in somebody could be interesting . . .

introducing the immovable leg.

No, it's stuck in three-dimensional space. If it's activated in someone's leg, they fiind themselves attatched to a stick that cannot move. Now, if they were falling and could hold onto the rod, then yeah, it'd make a nice way to stop in the air.

Now that I just realized that: elaborate setup where you have a bunch of Rods sewn into your clothes, like a weird harness. If you fall from a great height, you pull a rope you had rigged to activate the rods, and BLAMMO! You're stopped in midair with only slight major bruising everywhere.

Another one: If you get swallowed whole by something that moves fast (say, a Roc or something) wait untill it starts moving really fast, and then activate a rod. OUCH!

Then, of course, there is the "use 2 rods to climb to any height" trick, but I'd add something more to that. Sovereign Glue 2 metal gauntlets to the Rods so that the thumb can still move and reach the button. Strap yourself in tight to the gauntlets, and you've got a perfect climbing kit.

Iudex Fatarum
2007-12-31, 01:15 AM
my personal favorite is casting invisibility on a rod in the middle of a doorway at neck hight, or at knee hight, get the bad guys to chase my character and have him jump them, now all the bad guys are prone. if you do it right you might not even need the invisibility. after all they are distracted by the character.

triforcel
2007-12-31, 03:37 AM
I think my favorite use that I've heard of was a Lich taking his phylactery, blindfolding himself, flying to a random location in a random portion of the sky, and setting it amidst a bunch of Immovable Rods set into a box shape. Then, he'd cast a Permanency-Invisibility combo on all of them (and the Phylactery) and finally Permanency-Magic Aura on all of them and the Phylactery to make them undetectable.

That does sound like fun, until the Lich is destroyed. Then he regenerates next to his phylactery. Then he falls and takes massive falling damage. Then he regenerates next to his phylactery. Granted that isn't necessarily how it happens in your campaign, but that's always how I've seen it play out.

Slightly more on topic, I like to use them to impede the movement of enemies. Just place a few around a key area of the persons body, such as his wrists or even better his neck if he can't reach it with his hands, and he's pretty much stuck and you're free to do whatever it is you need to do.

Xefas
2007-12-31, 04:34 AM
That does sound like fun, until the Lich is destroyed. Then he regenerates next to his phylactery. Then he falls and takes massive falling damage. Then he regenerates next to his phylactery. Granted that isn't necessarily how it happens in your campaign, but that's always how I've seen it play out.

Slightly more on topic, I like to use them to impede the movement of enemies. Just place a few around a key area of the persons body, such as his wrists or even better his neck if he can't reach it with his hands, and he's pretty much stuck and you're free to do whatever it is you need to do.

I've never actually done/had it used in one of my campaigns, only saw it discussed during one of the "I'm playing a Lich. How do I make sure there's absolutely no way a DM could conceivably destroy my Phylactery without looking like a totally unreasonable prick in front of everyone?" threads that appear on the Wizards forum boards from time to time.

Though, I think I would rule that, since the body must be regenerated on to something, he'd be brought back sitting on the box of rods (Forgot they also said to hide a spare spellbook up under the Phylactery so one could adequately prepare to go seek vengeance and reclaim their old one). But, that's assuming you use the same Oots-style Lich regeneration I do.

One finger at a time...

Hasivel
2007-12-31, 09:13 AM
That does sound like fun, until the Lich is destroyed. Then he regenerates next to his phylactery. Then he falls and takes massive falling damage. Then he regenerates next to his phylactery. Granted that isn't necessarily how it happens in your campaign, but that's always how I've seen it play out.
The Lich needs feather fall, then.

In addition to making a ladder, two immovable rods with a hammock between them can make a safe(r) spot to sleep when your DM has banned rope trick and magnificent mansion. It can make a decent place to rest when you're out of range of most weapons.
It's not foolproof and I wouldn't do it without the aforementioned feather fall or ring of the same, however.

Citizen Joe
2007-12-31, 10:25 AM
One issue I've had with the immovable rod is what is the frame of reference for its immovability. I typically rule that it is based on the object with the largest gravitational effect. Usually that means the planet that you're on. However, for those that use Spelljammer, once outside the range of a planet, it would anchor to your ship instead (at least until you get within range of a larger mass).

Anyway, an immovable rod can be moved, slowly, with difficulty so trying to stop a very large object isn't completely valid... although it would definitely hinder it.

malagigi
2007-12-31, 12:07 PM
Yes, it would generally suck to put an immovable rod in place, and shortly there after have it grind into the crust of the planet until either broke or ground through to magma. On the other hand, it's one way to dig a well and you'd shortly have hot water for tea.

Alternatively, it would wander off into the sky... possibly to hit the planet in a little less than a year (depending on star drift).

...

What game are we playing again?

loopy
2007-12-31, 09:49 PM
I've got an immovable rod... In my PANTS! :smallwink:

...

I went to see the doctor about it, the prognosis isn't good. :smallfrown:

Fuzzy_Juan
2007-12-31, 10:07 PM
most amusing use of immovable rod...

character is flying and being chased by a dragon that is catching up and is going to eat me...pull out immovable rod, press button and let go as it gets close and opens it's mouth...laugh as DM tries to picture what we all know is going to happen...

over the lips and past the gums look out stomach...:smallbiggrin:

Galathir
2007-12-31, 11:08 PM
One of my friends was in a campaign where there was a deep ravine in the middle of a path. The party was being chased by a group of evil bad guys. The PCs jumped across the ravine then left an invisible immovable rod over it, neck height. Sure enough, the first guy took a running jump across and got clotheslined and dropped down about 10d6 worth of damage. The next guy did the same thing before the others caught on.

serpent615
2008-01-01, 02:26 PM
;3728241']Surgically implanting it in somebody could be interesting . . .

introducing the immovable leg.

i was waiting for that comment to come up...they WERE implanted inside me, but altered so that as long as i touched a surface, I was totally immovable...I was then surrounded by a spionic barrior that could absorb and return physical damage up to double my concentration check.

kjones
2008-01-01, 02:33 PM
My players use them all the freaking time. I'm constantly split between being impressed at their creativity and being really freaking annoyed by having all my devious plans ruined by their ingenuity. The most recent was when they used it to stop a crushing ceiling trap... oh, immovable rods, is there anything you can't do?

Reinboom
2008-01-01, 02:37 PM
I rather enjoyed the homebrewed Immovable Arrow.

I could also imagine, with correct application of immovable rods and sovereign's glue, one could make a floating city.

@v
Ok, a lot of immovable rods.

Anybody know the maximum weight of a standard sized floating city?

Citizen Joe
2008-01-01, 02:40 PM
Immovable Rod

This rod is a flat iron bar with a small button on one end. When the button is pushed (a move action), the rod does not move from where it is, even if staying in place defies gravity. Thus, the owner can lift or place the rod wherever he wishes, push the button, and let go. Several immovable rods can even make a ladder when used together (although only two are needed). An immovable rod can support up to 8,000 pounds before falling to the ground. If a creature pushes against an immovable rod, it must make a DC 30 Strength check to move the rod up to 10 feet in a single round.

A lot of people seem to be forgetting these limitations... a crushing ceiling trap weighs more than 4 tons and thus it would likely just kill the rod.

Adumbration
2008-01-01, 02:42 PM
Player: "Is Immovable Rod immovable in relation to the planet or the universe?"
DM: "... Wait, what? ... Do I want to know?"

Ditto
2008-01-01, 03:14 PM
We were on a train ('lightning rail'), with a secured back compartment that I (gnome sorcerer) and another PC both wanted to get into for separate reasons. Guy marches up to the guard and asks politely to be let in. He vaguely explains there's something of interest back there, possibly dangerous. (Neither of us have any idea of what it actually is.) My gnome casts Dancing Lights and starts is swirling about his hands, which prompts the guard to draw his gun and ask Guy to stop casting. Guy is not a caster, and very confused. My gnome (somehow) slinks past the two of them on the gangplank between the train cars and is about to walk into the rear. Unforunately, Guy spots me and holds me dangling in midair. "A-ha!" he says. "Nefarious bad-doings are afoot!"

Punchline: My gnome pulls out an Immovable Rod and thwip! is pulled off the side of the train, out of Guy's grasp. Meanwhile, all the guard saw was 'Gnome gone, Guy still has glowing flashy hands'. "Sir! You just VAPORIZED that GNOME!" It got messy for him then.

Luckily, I made the Strength check I needed to grab onto the rear of the moving train when I disengaged the rod a few seconds later.

Icewalker
2008-01-01, 03:18 PM
;3728241']Surgically implanting it in somebody could be interesting . . .

introducing the immovable leg.

Actually, the biggest use I've ever considered for them is some kind of super assassin, implanting one in each fore-arm, so he can climb through the air.

Shraik
2008-01-01, 03:24 PM
My idea was Put them in a Warforged's Compartments. Leave 'em in there so it is now the immovable warforged.

Shraik
2008-01-01, 03:34 PM
I think my favorite use that I've heard of was a Lich taking his phylactery, blindfolding himself, flying to a random location in a random portion of the sky, and setting it amidst a bunch of Immovable Rods set into a box shape. Then, he'd cast a Permanency-Invisibility combo on all of them (and the Phylactery) and finally Permanency-Magic Aura on all of them and the Phylactery to make them undetectable.

Wouldn't that mean when he regenerates he'd be trapped in the box of immovable Rods?

Fuzzy_Juan
2008-01-01, 08:53 PM
well yeah, but that is kinda the point...someplace nice and safe. If he can't get out of the place, then he is an idiot...he just needs to move some rods then put them back after he climbs out. A spare spellbook in the 'box' will allow him to prepare some spells to get out as well and either fly or just teleport to a place where he can properly prepare for getting back at those darn adventuring types.

Xyk
2008-01-01, 11:06 PM
We were on a train ('lightning rail'), with a secured back compartment that I (gnome sorcerer) and another PC both wanted to get into for separate reasons. Guy marches up to the guard and asks politely to be let in. He vaguely explains there's something of interest back there, possibly dangerous. (Neither of us have any idea of what it actually is.) My gnome casts Dancing Lights and starts is swirling about his hands, which prompts the guard to draw his gun and ask Guy to stop casting. Guy is not a caster, and very confused. My gnome (somehow) slinks past the two of them on the gangplank between the train cars and is about to walk into the rear. Unforunately, Guy spots me and holds me dangling in midair. "A-ha!" he says. "Nefarious bad-doings are afoot!"

Punchline: My gnome pulls out an Immovable Rod and thwip! is pulled off the side of the train, out of Guy's grasp. Meanwhile, all the guard saw was 'Gnome gone, Guy still has glowing flashy hands'. "Sir! You just VAPORIZED that GNOME!" It got messy for him then.

Luckily, I made the Strength check I needed to grab onto the rear of the moving train when I disengaged the rod a few seconds later.

wow. You have convinced me to give all my characters immovable rods when affordable. That is the best thing i've ever seen. Congratulations.

Collin152
2008-01-01, 11:20 PM
Hm. I think whether the rod is immovable in relation to the earth is moot, but to determine that, something must be answered first:

How high is the Earth's Gravity's Strength score?

Goats_o_Mjolnir
2008-01-01, 11:24 PM
I remember turning 3 of em invisible in a line across a small alley and watching my pursuers get clotheslined, good times

Collin152
2008-01-01, 11:33 PM
Chalk that up one the List of Essential Adventuring paraphenelia: A permanently invisible Immovable Rod, conveniently stored within its own carry case.

Altharis
2008-01-01, 11:59 PM
I just have one little thing to point out: Implanting an Immovable Rod into any part of the body is a very good way to have a giant chunk ripped out of that body part!

Think about it: If you move your Assasin's Immovable arms, the arms move, but the rod inside many layers of flesh and bone doesn't. Eww....

That said, it makes a good weapons if you can get it into someone's body. For example a crossbow with spiked immovable rod bolts, or....well I'll leave the rest to your imagination. :smallamused: You sickoes.

*Doffs hat to best Adventuring equipment...ever!*
Altharis

Goats_o_Mjolnir
2008-01-02, 12:02 AM
Theres a bright and messy future for my bloodmage >:D hehehehe

Ganurath
2008-01-02, 02:05 AM
Slip one between the Paladin's mount and the saddle while it's strung up outside the inn if you're the sealthy type.

If your the muscle puncher type, use it in interrogation. Think levitating chair meets dropping the soap.

Of course, you may be the more pious healer character. In this case, a few of these make a portable medical bed.

Ah, let's not forget what the arcanist can do with this: Have fun playing with planar physics by activating one inside a portable hole or bag of holding.

BRC
2008-01-02, 02:10 AM
Put one in the shaft of a spear, somebody starts charging you, set spear against charge and turn on the immovable rod, then BOOK IT!

Naleh
2008-01-02, 03:14 AM
"Winged Boots? Ha! I have two Immovable Rods!"

I know, it's the obvious one, but I couldn't resist...

Epic_Wizard
2008-01-02, 09:24 AM
Hm. I think whether the rod is immovable in relation to the earth is moot, but to determine that, something must be answered first:

How high is the Earth's Gravity's Strength score?

Doesn't really matter unless you drop something on the rod but for fairly static objects it's 8000 lbs.


A lot of people seem to be forgetting these limitations... a crushing ceiling trap weighs more than 4 tons and thus it would likely just kill the rod.

8000lbs IS 4 tons...

Actually I think that most of those traps have strength scores to prevent them from moving down in a given round so you just need to have enough immovable rods who's combined strength scores are greater than that needed to stop the ceiling from moving.

I think that I like the idea of creating a thrown spear, impact activated, version that causes additional damage if the creature doesn't carefully remove himself from the spear. This could also be combined with effects that give the spear temporary magical effects to create a 1 shot potent weapon.

Oh here is a REALLY good one. Goad your big bad enemy into trying to grapple a Rogue in Plate armor that has a Potion or Oil compartment (from Dungeonscape) filled with Sovereign Glue and enchanted to function like an immovable rod. The Rouge has applied an Oil of Sliperyness before getting in the armor which protects her when she causes the sovereign glue to spray all over her and the armor. She then activates the Immovable Rod feature of the armor and uses an Escape Artist Check (with a nice bonus from the Oil of Sliperyness) to get out of the armor which is then stuck to the enemy who is also tethered to that point in space. :smallbiggrin:

fendrin
2008-01-02, 10:05 AM
8000lbs IS 4 tons...
Well, it's 4 short tons, not to be confused with metric tons (aka tonnes) or long tons.

Of course, here in the US, an unlabeled ton is generally a short ton.

Funny new 'cursed' item: the 'really-hard-to-move rod'. Functions just like an immoveable rod, except it's only a DC 15 str check to move it, it only holds 400 lbs, and the weight limit drops by 10 lbs for every foot off the ground it is...


Oh here is a REALLY good one. Goad your big bad enemy into trying to grapple a Rogue in Plate armor that has a Potion or Oil compartment (from Dungeonscape) filled with Sovereign Glue and enchanted to function like an immovable rod. The Rouge has applied an Oil of Sliperyness before getting in the armor which protects her when she causes the sovereign glue to spray all over her and the armor. She then activates the Immovable Rod feature of the armor and uses an Escape Artist Check (with a nice bonus from the Oil of Sliperyness) to get out of the armor which is then stuck to the enemy who is also tethered to that point in space. :smallbiggrin:

Or you know, just stick the button end in sovereign glue and grapple an enemy, pushing that end before the glue sets. The impact pushes the button. Enemy is glued to the rod, the button is encased in glue, and you don't have to slither your way out of stiffened fullplate (which, as DM, I would say would be nigh impossible, say DC 50).

Of course, by the time either of these become financially practical, there are better options.

SexyOchreJelly
2008-01-02, 10:10 AM
It is a cool item I have never had the chance to use.


*Cries in a corner.* (Luckily there are several ways to use it demonstrated on this thread... mwahahaha!!!)

Sebastian
2008-01-02, 10:55 AM
Just remember, it is a immovable rod, not a indestructable rod, so putting it to stop a crushing ceiling or in front of a runnig ship/train or similiar is more probable to destroy the rod than the other thing.

Citizen Joe
2008-01-02, 11:31 AM
Ceiling trap > 4 tons
4 tons = 8000 lbs
Weight limit on I.R. = 8000 lbs
thus ceiling trap > I.R. weight limit.

I was considering that I.R. Sovereign Glue trick... If the rod/glue capsule/button was designed with fletchings, you could fire it as a crossbow bolt. It could be a really neat way of stopping a run away carriage.

Epic_Wizard
2008-01-02, 12:32 PM
Just remember, it is a immovable rod, not a indestructable rod, so putting it to stop a crushing ceiling or in front of a runnig ship/train or similiar is more probable to destroy the rod than the other thing.

The rod would just take ramming damage along with the fast moving object in question. In the case of a ship this is easy since the hull section that the rod makes contact with would take the damage, which is probably enough to destroy it, and depending on where the rod is placed the remaining damage would be dealt to the next section that the rod runs into until the damage is expended and the ship stops moving. Multiple rods would probably spread the damage out.

Of course if the damage dealt by the collision with the first hull section, the damage is dealt to both objects that take part in the collision, is enough to destroy the rod then no further damage would be dealt.


Well, it's 4 short tons, not to be confused with metric tons (aka tonnes) or long tons.

Of course, here in the US, an unlabeled ton is generally a short ton.

Funny new 'cursed' item: the 'really-hard-to-move rod'. Functions just like an immoveable rod, except it's only a DC 15 str check to move it, it only holds 400 lbs, and the weight limit drops by 10 lbs for every foot off the ground it is...



Or you know, just stick the button end in sovereign glue and grapple an enemy, pushing that end before the glue sets. The impact pushes the button. Enemy is glued to the rod, the button is encased in glue, and you don't have to slither your way out of stiffened fullplate (which, as DM, I would say would be nigh impossible, say DC 50).

Of course, by the time either of these become financially practical, there are better options.

I'm pretty sure that they are referring to 'small tons'

The cursed item idea is intriguing and could provide an interesting couple of encounters before the PC's realize what they have.

The SRD entry for Sovereign Glue (http://www.systemreferencedocuments.org/35/sovelior_sage/magicItemsWI.html#sovereign-glue) states that it takes the glue 1 round to set and I think you would be hard pressed to keep the rod stuck to an individual for a full round let alone one strong enough that you would want him immobilized like this.

While you are correct that it would be difficult to wiggle out of a normal suit of full plate (donning armor rules (http://www.systemreferencedocuments.org/35/sovelior_sage/armor.html#table-donning-armor))
First of all the Oil of Slipperyness gives you a +20 to Escape Artist checks and since it is inside of the armor it would not affect the grapple check you opponent has to make. As for the wriggling out you could have a halfling under the effects of a Growth spell to become Medium Sized don the armor and then you simply dismiss the spell which would shrink her to a size where she could escape the armor. Plus the Sovereign Glue would basically fuse the armor together and prevent it from falling apart when you get out of it.

Actually I was thinking of this in terms of Demogorgon from the end of the Savage Tide adventure path that ran in Dungeon Magazine for the twelve months before its (unfortunate :smallfrown: ) move to the web. However, this would be effective against anyone who is a strong grappler or has improved grab. (can us say "I glued the Tarrescue's mouth shut and now it can only move ten feet per round with a strength check"?) :smallbiggrin:

fendrin
2008-01-02, 01:18 PM
The cursed item idea is intriguing and could provide an interesting couple of encounters before the PC's realize what they have. The best part about it is that it only is 'cursed' to metagamers. Anyone who takes the time to experiment a little will know that it is a weaker version.


The SRD entry for Sovereign Glue (http://www.systemreferencedocuments.org/35/sovelior_sage/magicItemsWI.html#sovereign-glue) states that it takes the glue 1 round to set and I think you would be hard pressed to keep the rod stuck to an individual for a full round let alone one strong enough that you would want him immobilized like this. When I said 'grappled' I should have said 'pinned'. Of course, the timing difficulties apply to your original idea as well.


While you are correct that it would be difficult to wiggle out of a normal suit of full plate (donning armor rules (http://www.systemreferencedocuments.org/35/sovelior_sage/armor.html#table-donning-armor))
First of all the Oil of Slipperyness gives you a +20 to Escape Artist checks and since it is inside of the armor it would not affect the grapple check you opponent has to make. As for the wriggling out you could have a halfling under the effects of a Growth spell to become Medium Sized don the armor and then you simply dismiss the spell which would shrink her to a size where she could escape the armor. Plus the Sovereign Glue would basically fuse the armor together and prevent it from falling apart when you get out of it.

You are aware that full plate encases pretty much the whole body, right? the largest openings are significantly smaller than the wearer's head. I'm starting to think that DC 50 is way too low... No matter how good you are at slipping from bonds, you would not be able to get out of it. Maybe if someone was reduced to tiny size they could do it... If a character took the time to don full plate after being enlarged the battle would be mostly over by the time they were ready... and for that matter enlarge person only lasts 1 round per caster level, so it would take a high caster level to pull this off, at which point you have better options.


Actually I was thinking of this in terms of Demogorgon from the end of the Savage Tide adventure path that ran in Dungeon Magazine for the twelve months before its (unfortunate :smallfrown: ) move to the web. However, this would be effective against anyone who is a strong grappler or has improved grab. (can us say "I glued the Tarrescue's mouth shut and now it can only move ten feet per round with a strength check"?) :smallbiggrin:

I only played the very beginning of Savage Tide, so i'm not familiar with what you are referring to. The Tarrasque wouldn't have much of an issue because the glue wouldn't set until the armor/rod had been swallowed. At that point, the item would be destroyed in a round or two by the crushing and acid damage. Oh, and you would have little to no chance of escaping the armor) before getting swallowed.

Ganurath
2008-01-02, 01:40 PM
I only played the very beginning of Savage Tide, so i'm not familiar with what you are referring to. The Tarrasque wouldn't have much of an issue because the glue wouldn't set until the armor/rod had been swallowed. At that point, the item would be destroyed in a round or two by the crushing and acid damage. Oh, and you would have little to no chance of escaping the armor) before getting swallowed.Never mind that it's easier for the party Wizard to fly 200 feet over Mr. T, use telekinesis to hold out a slab of stone, and cast a sculpted wall of stone. Can you say 'rock falls, everyone dies?'

merrja666
2008-01-02, 01:57 PM
Spiked Immovable Rod - shove in into/inside something and activate.

Also - Immovable Spiked Chain - put it inside someone, and Immobalise it, and the victim cannot move (much).

Ranged Pin + Immovable Rods are good. An Immovable Rod Pinning someone's foot to the ground is always nice.

Epic_Wizard
2008-01-02, 02:10 PM
The best part about it is that it only is 'cursed' to metagamers. Anyone who takes the time to experiment a little will know that it is a weaker version.

Only if you tell the gamers that it's a different item since most cursed items are very hard to distinguish from their normal counterparts.


When I said 'grappled' I should have said 'pinned'. Of course, the timing difficulties apply to your original idea as well.

I assumed you meant pinned.


You are aware that full plate encases pretty much the whole body, right? the largest openings are significantly smaller than the wearer's head. I'm starting to think that DC 50 is way too low... No matter how good you are at slipping from bonds, you would not be able to get out of it. Maybe if someone was reduced to tiny size they could do it... If a character took the time to don full plate after being enlarged the battle would be mostly over by the time they were ready... and for that matter enlarge person only lasts 1 round per caster level, so it would take a high caster level to pull this off, at which point you have better options.

You could use Polymorph which has a longer duration and would allow you to 'switch places' with another member of the party for the trick to work. Failing this you could just make an Escape Artist check ahead of time to prepare the armor to make it easy to get out of.

Alternately and at the DM's discretion you could use your new position to attack the monster with any weapon you have at your disposal assuming you aren't pinned and your arms are free. Granted this would probably require freeing your arms from the Sovereign Glue but it could still work and would eliminate the need for escape from the armor or even a Rogue.


I only played the very beginning of Savage Tide, so i'm not familiar with what you are referring to. The Tarrasque wouldn't have much of an issue because the glue wouldn't set until the armor/rod had been swallowed. At that point, the item would be destroyed in a round or two by the crushing and acid damage. Oh, and you would have little to no chance of escaping the armor) before getting swallowed.

I actually just read the entire adventure without playing through it. I enjoy reading them and seeing how the plots develop and how I could defend against a given situation without knowing about it ahead of time. By this I mean as a Wizard what spells should I prepare and in what quantities that will probably be useful in a large majority of non-random encounters and a decent number of the random ones. For example casting Silence on the party Fighter and then staying 20ft away seems to be a good idea.

Here is another interesting question: What applications can we find for Immovable Rod(s) and a Reverse Gravity Field? Use anything else you like provided that the Immovable Rod(s) are a fairly integral part of the setup.

fendrin
2008-01-02, 11:06 PM
Only if you tell the gamers that it's a different item since most cursed items are very hard to distinguish from their normal counterparts.
As I described it, it would just be a weaker version. There are no ill effects unless you assume it is a true immovable rod.


You could use Polymorph which has a longer duration and would allow you to 'switch places' with another member of the party for the trick to work. Failing this you could just make an Escape Artist check ahead of time to prepare the armor to make it easy to get out of.
Honestly, if you;re going to polymorph, you might as well do something else. I mean really, it's polymorph. The escape artist thing requires DM discretion.


Alternately and at the DM's discretion you could use your new position to attack the monster with any weapon you have at your disposal assuming you aren't pinned and your arms are free. Granted this would probably require freeing your arms from the Sovereign Glue but it could still work and would eliminate the need for escape from the armor or even a Rogue.
New position? I'm not sure what you are referring to...

Here is another interesting question: What applications can we find for Immovable Rod(s) and a Reverse Gravity Field? Use anything else you like provided that the Immovable Rod(s) are a fairly integral part of the setup.

simple: use an IR to anchor yourself while sending everything else up with reverse gravity.

Randel
2008-01-02, 11:30 PM
Get one or more Decanters of Endless Water, attach them to the immovable rod and then you can activate the rod, then activate the decanter at full blast to make a fire hose you can put in place and leave.


Join or start up a circus, have the bars on the trapeze be immovable rods so that during tense moments the trapeze artists can swing up to the top of their swing. Freeze the rods in place, do some chin ups or climb up on top of the rod to do tricks, then go back down and unfreeze the rod to get back into their swing.


If you can somehow get it where trapeze artists can swing up over the top of the bar their trapeze is attached to, have two immovable rods, two skilled trapeze artists, some rope connecting the rods together and then let them swing their way across the landscape. Probably not the most efficient way to travel but it would probably be pretty darn cool looking.

Go to locked castle gate or other object you need a battering ram for. Put two immovable rods in place to suspend the heavy battering ram from and then just swing it right into the gate. Don't have to support the weight on your shoulder.

If you really need to keep a door barred, stick a metal plate on one side of the door and then put an immovable rod or two against it.

Attach one to a tower shield, if someone tries charging at you then just activate it.

Get a grappling hook, a spool of rope, some guiding rings and attach them to the immovable rod... create an immovable fishing rod for catching really strong fish.

Hectonkhyres
2008-01-03, 12:18 AM
We had an immovable rod mounted as the handle in one character's adamantine shield. The moment the frost giant swings its mace at you... *click*. It isn't going anywhere.

We also figured out how to mount the thing inside a special javelin. One second after it penetrates, a whole bunch of barbs pop out and it activates. It just ruins somebody's day, doesn't it?

Irreverent Fool
2008-01-03, 12:33 AM
I rather enjoyed the homebrewed Immovable Arrow.

I could also imagine, with correct application of immovable rods and sovereign's glue, one could make a floating city.

@v
Ok, a lot of immovable rods.

Anybody know the maximum weight of a standard sized floating city?

Check out the stronghold builder's guidebook. I think it actually mentions using immovable rod to build a floating castle.

obvious pun
2008-01-03, 01:03 AM
Immovable flying arena. 'Cause nothing says battle to the death like immovable flying arena.

Or, put it into a sword, put the sword into a stone, then have people line up to try pulling the sword out to become king.

Talic
2008-01-03, 02:41 AM
Immovable flying arena. 'Cause nothing says battle to the death like immovable flying arena.

Or, put it into a sword, put the sword into a stone, then have people line up to try pulling the sword out to become king.

So Arthur just found the button?

Everyone's talking about putting rods at clothesline height. Not feasible. That's different height for halflings, elves, and goliaths.

Try knee height. Easy to hop, and majorly painful for the sucka that hits it.

Epic_Wizard
2008-01-03, 08:39 AM
As I described it, it would just be a weaker version. There are no ill effects unless you assume it is a true immovable rod.

Unless you give it a different name then that is exactly what they will do. It may not sound like much but it is when the giant stone door you knew was going to slam down behind you that you held up with an immovable rod still slams down.


Honestly, if you;re going to polymorph, you might as well do something else. I mean really, it's polymorph. The escape artist thing requires DM discretion.

Yeah but Polymorph can't anchor a BBEG basically in place where your Wizards can set up all sorts of nasty on him. I mean seriously they could do things like Transmute Rock to Lava under him and there isn't much he could do to escape. Plus now it's a move action to move ten feet...


New position? I'm not sure what you are referring to...

Floating off the ground (remember BIG bad evil guy. You wouldn't need this against a medium creature really plus it wouldn't work) and possibly upside down. However, you are not moving and you are in a stable position unless the ugly you are attached to manages to move you.


simple: use an IR to anchor yourself while sending everything else up with reverse gravity.

I was hoping for something a little more creative... besides the area is given in cubes per level meaning you can arrange them however you like. Heck if you combined it with Telekinesis you could have a space equal to whatever the push distance is for that between the cubes and then get some REALLY crazy height. Oh and then you use your Telekinesis to push them off of the top of the area and then they go splat... :smallbiggrin:


We had an immovable rod mounted as the handle in one character's adamantine shield. The moment the frost giant swings its mace at you... *click*. It isn't going anywhere.

We also figured out how to mount the thing inside a special javelin. One second after it penetrates, a whole bunch of barbs pop out and it activates. It just ruins somebody's day, doesn't it?

I like this though it would require some determinations on the DM's part. Like a Dex check or Reflex save if try to move the thing 10 feet and walk with it without taking damage. Also the damage would probably be related to the original damage that the thing dealt. I mean if it only did 1 damage on your attack roll then either you hit the giant in the tip of a boil on his toe or you barely penetrated and therefore there will be fewer spikes inside the giant. Also you would have to determine where the thing hit the creature since if it hit a dragon in the neck turning its head could do damage.

Plus what is the maximum damage that the thing does before it has basically worked itself loose or destroyed the flesh around it?

This could be a very interesting formula. Also if I were a DM I would require that the thing fall to the ground after it is no longer stuck in a creature. Otherwise it would become a hazard in combat that probably doesn't have a definite placement and I would have to keep track of.

Ashlock
2008-01-03, 08:43 AM
Hilarious thread. It warms my heart to see the good ol' immovable rod in discussion. I actually used immovable rods as weapons in my book. :smallsmile: They needed some serious "screen time."

Khanderas
2008-01-03, 08:48 AM
Immovable bracers. For prisoners, no button but keys required. (No need to chain a prisoner to a bolted wall. Just put him where you want him.)

serpent615
2008-01-03, 09:57 PM
Hilarious thread. It warms my heart to see the good ol' immovable rod in discussion. I actually used immovable rods as weapons in my book. :smallsmile: They needed some serious "screen time."

Well, thank you...I was hoping for some good stuff when I started it.

Epic_Wizard
2008-01-04, 07:58 AM
Immovable bracers. For prisoners, no button but keys required. (No need to chain a prisoner to a bolted wall. Just put him where you want him.)

I really like this idea especially since there would be 2 bracers and thus it would be harder to move. Question about that by the way. Would you have to make 2 DC30 Strength checks or would you make one larger check and if so what would be the DC of the check?

OOO here is a good one. You enchant a bunch of small stones (think flat-ish stones about 2-3 inches in diameter) as if they were ammunition but they are triggered by tossing a bunch of them into a five foot space where they then stick in mid air. It requires an Escape Artist check (DC 25 for a Large creature with the DC decreasing by 5 for every size you are smaller than Large down to Tiny at which point there is no obstruction from moving through the stones since you can slip between them easily) to move through a square full of these stones with failure indicating that you are stuck in the square containing the stones and are considered flat footed. A creature at least 2 size categories larger than the area of the stones can move through them as though they were difficult terrain. If a Huge or larger creature's move takes him through an unbroken area of the stones that is as large as his widest two dimensional area that is parallel to the stones then he must make a DC 30 Str check to move through the stones for every five feet for which the stones meet these conditions. Any creature inside of an area of the stones or who is being attacked through an area of them receives partial cover. A Targeted Dispel magic can affect one five foot square of the stones per casting.

Wow that turned out to be longer than I anticipated.

Tokiko Mima
2008-01-04, 10:54 AM
This thread just gave me a great idea for a cursed item version of immovable rod. It would work the same as a normal immovable rod, but what it is immovable in relation to is determined completely at random. It could be fixed with relation to the user, the user's planet, a random NPC/monster somewhere, the sun, the galaxy, the universe, a photon of light somewhere, etc. :smalltongue:

serpent615
2008-01-04, 11:34 AM
I really like this idea especially since there would be 2 bracers and thus it would be harder to move. Question about that by the way. Would you have to make 2 DC30 Strength checks or would you make one larger check and if so what would be the DC of the check?

OOO here is a good one. You enchant a bunch of small stones (think flat-ish stones about 2-3 inches in diameter) as if they were ammunition but they are triggered by tossing a bunch of them into a five foot space where they then stick in mid air. It requires an Escape Artist check (DC 25 for a Large creature with the DC decreasing by 5 for every size you are smaller than Large down to Tiny at which point there is no obstruction from moving through the stones since you can slip between them easily) to move through a square full of these stones with failure indicating that you are stuck in the square containing the stones and are considered flat footed. A creature at least 2 size categories larger than the area of the stones can move through them as though they were difficult terrain. If a Huge or larger creature's move takes him through an unbroken area of the stones that is as large as his widest two dimensional area that is parallel to the stones then he must make a DC 30 Str check to move through the stones for every five feet for which the stones meet these conditions. Any creature inside of an area of the stones or who is being attacked through an area of them receives partial cover. A Targeted Dispel magic can affect one five foot square of the stones per casting.

Wow that turned out to be longer than I anticipated.



first of all....I like it
However, it will take some serious DM fudging, as well as allot of gold...unless there’s a command word to turn them off.

FlyMolo
2008-01-04, 11:54 AM
This thread just gave me a great idea for a cursed item version of immovable rod. It would work the same as a normal immovable rod, but what it is immovable in relation to is determined completely at random. It could be fixed with relation to the user, the user's planet, a random NPC/monster somewhere, the sun, the galaxy, the universe, a photon of light somewhere, etc. :smalltongue:

I detect future hilarity. " I push the button on the immovable rod." "It takes off straight up at the speed of light. Make a reflex save."

serpent615
2008-01-04, 12:57 PM
I detect future hilarity. " I push the button on the immovable rod." "It takes off straight up at the speed of light. Make a reflex save."

Player: "oooo, i got a natural 20 on an epic Mo...did i make it?"
DM: ".....no" *DM rolls alot of dice* (Dmg)

D Knight
2008-01-04, 04:01 PM
Player: "oooo, i got a natural 20 on an epic Mo...did i make it?"
DM: ".....no" *DM rolls alot of dice* (Dmg)

Player: " OOO great this might hurt alot in a few seconds."
DM: "Yes it will i am almost done rolling" laughting like a mad person
Player: "i hope i can survive this" dice rollling in background "Ahhh" under breath

this form has been making me laught and cry all week. Thank you all.

serpent615
2008-01-04, 05:49 PM
I was wondering...on a Monk with 17 ranks in tumble, do you think I could do acrobatics in the air with 2 rods?

cus that's where i am now...

GoC
2008-01-04, 07:30 PM
I just have one little thing to point out: Implanting an Immovable Rod into any part of the body is a very good way to have a giant chunk ripped out of that body part!

Think about it: If you move your Assasin's Immovable arms, the arms move, but the rod inside many layers of flesh and bone doesn't. Eww....

The arms just don't move. Period.
If someone was holding your bones in place you wouldn't be able to rip the remains of your arms free would you?

Collin152
2008-01-04, 08:07 PM
True... But what if you could will the rods to become immobile?

Megafly
2008-01-04, 08:45 PM
with a command word activation rather than a button and some kind of harness you could have a FB in your party and not be afraid of getting sliced and diced every combat.

Signmaker
2008-01-04, 09:08 PM
The arms just don't move. Period.
If someone was holding your bones in place you wouldn't be able to rip the remains of your arms free would you?

Yes, you could. It would just hurt a LOT.

One idea would be that attempting to yank your limb that was rodded would result in tearing several muscles, ligaments, etc.

Also, if, say, a giant decided to grab you and pull, yeah, ripped.

Epic_Wizard
2008-01-04, 09:09 PM
first of all....I like it
However, it will take some serious DM fudging, as well as allot of gold...unless there’s a command word to turn them off.

They would be a one use item that would last for probably a few minutes. Good for causing not nice things to happen to pursuers though. Just drop those all across the hallway and then set a Summon to go off that summons a slime big enough to cover the entire hallway. It can pass through the stones without a problem and if you summon the right slime then it won't harm the stones.

The spell that basically sets a trigger condition for a spell in an area is in the Spell Compendium and probably somewhere else. I know it's in the Spell Compendium though since I remember reading it last night.


The arms just don't move. Period.
If someone was holding your bones in place you wouldn't be able to rip the remains of your arms free would you?

Yeah but there is still the Strength check to move the rods ten feet that could damage you. Plus your arms, probably just your forearms actually, are stuck in place but the rest of you can move about. If someone bull rushed you while stuck like that then they could easily rip your elbows or shoulders (or whatever joint is just after the anchoring effect stops) out of their sockets and possibly off of your arms. That would NOT be pretty.

Random thoughts here: We discussed activating the rod inside the gut of a creature that swallowed you (I think). Well 2 things, first what about using immovable rods to hold the hole you create shut? You could even probably anchor them to the hole's sides which would also prevent the creature from moving.

Second what happens if you do something nasty like cast Blade Barrier while INSIDE of a creature? Or some other spell that does slashing damage? I think there is at least one outside of the SRD list that is a cone or burst. if THAT doesn't deal enough slashing damage for you to get out then I don't know what would. Heck anything that went off like that in a stomach would shred it.

Irreverent Fool
2008-01-04, 09:16 PM
Second what happens if you do something nasty like cast Blade Barrier while INSIDE of a creature? Or some other spell that does slashing damage? I think there is at least one outside of the SRD list that is a cone or burst. if THAT doesn't deal enough slashing damage for you to get out then I don't know what would. Heck anything that went off like that in a stomach would shred it.

The creature takes damage as normal for the spell (despite you being surrounded on all sides by its stomach lining) and if you deal enough damage, you get out. Despite the obvious implications of dealing a bunch of damage to a critter's innards, hp are hp, no matter where it's coming from. There's no reason cutting your way out with a spell would be any different than cutting your way out with a light slashing weapon. Of course, some DMs will say otherwise, so bear that in mind before swallowing anything whole. Moral of the story: Chew your food.

nimby
2008-01-04, 09:17 PM
Gradually replace all your bones with immovable rods/bone prosthetics. Someone wants to bash your head in? Head's not gonna move. Stab you in the chest? Immovable ribs, suckah.

Big mace crashing on your arms? You're gonna be bruised, maybe have some missing skin, but your arms will still be intact!

Signmaker
2008-01-05, 12:26 PM
Gradually replace all your bones with immovable rods/bone prosthetics. Someone wants to bash your head in? Head's not gonna move. Stab you in the chest? Immovable ribs, suckah.

Big mace crashing on your arms? You're gonna be bruised, maybe have some missing skin, but your arms will still be intact!

But then, how would you activate/deactivate? Customize for command word?

I'm somewhat reminded of Tekkai from One Piece, the hardening of muscles to resist a blow.

Randel
2008-01-05, 09:45 PM
Gradually replace all your bones with immovable rods/bone prosthetics. Someone wants to bash your head in? Head's not gonna move. Stab you in the chest? Immovable ribs, suckah.

Big mace crashing on your arms? You're gonna be bruised, maybe have some missing skin, but your arms will still be intact!

If you are going to be replacing bones and such... just replace them with adamantine, having really hard bones should be at least if not more useful than having immovable ones.

If you can somehow get immovable rods that activate at a distance, attach one to a length of rope. It could act like a grappling hook you don't need to grapple anything with. Get a way to launch the rods outward and with two you could swing around like Spider-man, no need to attach your ropes to buildings, just swing from the rods you put in place.

Citizen Joe
2008-01-05, 09:47 PM
You know there is a spell that grants flight...

icthius
2008-01-05, 10:15 PM
One of my players is an acrobat in a circus, and he uses these as part of his act. My BBEG is going to be an artificer, and is going to disenchant one of them ahead of time to see if he can kill him...

Collin152
2008-01-05, 10:44 PM
You know there is a spell that grants flight...

yeah, but wheres the class? The sense of acomplisment?

FlyMolo
2008-01-05, 10:51 PM
yeah, but wheres the class? The sense of acomplisment?

The tumble checks? the risk of death? Those are far cooler. Also, fly has a duration.

serpent615
2008-01-05, 10:58 PM
The tumble checks? the risk of death? Those are far cooler. Also, fly has a duration.


along the same lines, how could tumbling thru the air aid in combat, because it would have to have some advantage...(in real life it would at least, idk about D&D basis) what I mean is, say tumbling up and doing a drop kick from above, wouldn’t that add dmg? though I’d say that would be a move and only get that 1 attack

Foolosophy
2008-01-05, 11:35 PM
along the same lines, how could tumbling thru the air aid in combat, because it would have to have some advantage...(in real life it would at least, idk about D&D basis) what I mean is, say tumbling up and doing a drop kick from above, wouldn’t that add dmg? though I’d say that would be a move and only get that 1 attack

if you adopt the Iron Heroes Stunt System you can get some neat increases (+2 attack or +1 dmg or more if you are willing to incurr a skill check penalty) with succesfull jump/tumble/balance checks

serpent615
2008-01-06, 12:09 AM
if you adopt the Iron Heroes Stunt System you can get some neat increases (+2 attack or +1 dmg or more if you are willing to incurr a skill check penalty) with succesfull jump/tumble/balance checks

is Iron Heros a book?, i wana look into it now. If not, where is it?

Int -1
2008-01-06, 08:38 AM
Where do I start with this tale? In order to understand a little bit of the actions of the NPC's I need to explain something about the world our characters were in. Instead of beginning in a tavern our characters (3 of them) started up side down in a cage waiting for be ritually slaughtered. We were level 1 at the moment. We escaped fortunately and found ourselfs joining up with an Half-Orc Fighter. I was an Wizard and the other two were an Bard and a Rogue.
We were on a broken bridge. On the one end there was a dark forrest which scared us, on the other end (which we couldn't reach) there was a city. The cleric who wanted to slaughter us wanted to get in the city and we were interested in that dark, on-the-other-side-of-the-(100 meter)gap-in-the-bridge city. We could barely see an other bridge far away because around the city there was a kilometer wide (and very deep) sort of moat with four bridges, which, when we got by the other bridge were probably all broken.
Having depleted our recourses we need to find food and we decided to go into the dark, scary forrest. After a few sessions we got an the other side of the forrest and found a little village of gnomes. Quickly we learned that those gnomes were fanatically about reaching the city. They had a plan which envolved a catapult and a gnome which was going to be catapulted over the 100 meter gap. We understood that that was utterly stupid but we didn't want to miss it for the world, so we helped them making preperations and secured a stronghold in the deep dark forrest (in which I found two immovable rod and two rings of jumping (which, as roy's ring, just went straight up)
After a few other sessions the gnomes got through the forrest with substantial losses but prepared their catapult anyway. The plan was to shoot one gnome to the other side with a rope so more could go to the other side. We were still smiling at this plan. The gnome however had a parachute which should do the job of a soft landing. They just had to align the catapult, aim the bloody thing and shoot him.
If anything went wrong that would mean certain death. The moat around the city was very very deep and consisted, as we were told, by a liquid which meant instant death.
One of the Gnome NPC leaders decided all was good and fired the gnome. At first things were looking good, but then I saw that the gnome was falling short. In a quick reaction I did something very unusual; I tried to save the Gnome. Although he was falling short, the gnome had bumped into the bridge and with its speed it had he died. But I didn't see that, because I was already acting.
The entire campaign I did nothing like saving someone. I had only damage spells (I did not find any spellbook, and I had to survive) and was not even thinking about saving anyone. But I did. And it was profoundly stupid.
The gnome was falling now, but still had a rope around its waist. Just pulling the rope to get him back was not an option; he had to much speed, he would going to crash into the wall of the moat (under where we were standing (on the bridge)). So I got the rope, secured it to me and used my ring of jumping.
That created a situation I didn't expected. I had assumed that the jumping ring was just going to go upwards. But the dm told me that because of the weight the gnome had (and the speed) both of us were going to the middle of the gap in the bridge. That shocked me because Fly wasn't a spell I prepared.
I remembered the immovable rod and I activated it. That consolidated me and the gnome. Both of us were in the middle of the gap; I sat on a Immovable rod somewhere 30 meters above the bridge and the gnome liveless hanging on the rope 30 meters below the level of the bridge.
The dm said to me that the gnome had bumped into the bridge and was dead. So far for my rescue operation. So I cut the Gnome loose. But now I had to be rescued. The immovable rod was not a very good chair so I couldn't hold on long. So the Half-Orc Fighter shot a few arrows with ropes on them. Most of them didn't get near, but one did and I lunged for one. Happily I made the check and got the rope; but I was falling now. The rope was secured and the Half Orc was pulling in the rope as a madmen.
Somewhere my fall must stop and the moment it did I had to roll an strength check well above my normal abillities. (my strength score was my dump score) but I made it. I run around screaming, overjoyed with the succes.
The rest of the day I spend with drinking up my supply of wine. Lawful stupid, but we still have to laugh about the story.:smallbiggrin:

daggaz
2008-01-06, 09:18 AM
Destroying ships (Activate one in the path of a galleon and watch as it punches a hole through the hull from bow to stern)



Im pretty sure the ship will make its strength check and just move the rod.. The DC isn't that high.

Naleh
2008-01-06, 03:06 PM
Im pretty sure the ship will make its strength check and just move the rod.. The DC isn't that high.

Maybe, but even if it did, it would slow the ship down. A lot.

ealan
2008-01-06, 03:31 PM
Lock my door at night. Lock my windows at night.

Hiding the body of a fallen comrade in some clouds... Clouds move my character soon found out.

Creating the prison with no walls... lots of straight jackets with rods sovereign glued to them. I carried one in a former campaign so when we stopped at night we didn't have to tie the prisoner we just jacket him in place.

Artanis
2008-01-06, 04:06 PM
Some ideas:


Triggers for really nasty traps.
--Place one underneath a trap door, with the button sticking up through the door to look like a normal nail or rivet. When somebody steps on it, the rod deactivates, allowing the trap door to fall.
--Place several under a large rock trap weighing up to 7999 pounds. The PCs remove the first one very very carefully, and when nothing happens, start removing the others. When the last one is removed...*splat*

Siege weapons.
--Use one to anchor a siege weapon like a Ballista, thereby removing the recoil and allowing the weapon to pummel a certain spot in the wall over and over, punching through sections that one shot may be insufficient for.
--Use one as part of the weapon's crank so that instead of a locking mechanism, the crew primes the weapon and pushes the button. When it's time to fire, they just push the button again (preferably with a stick or something) and let the weapon fire.

Siege defenses.
--Use a bunch to anchor gates and such. While a battering ram will no doubt move one immovable rod, it'd have a hard time busting through a couple dozen.
--Use some to anchor weapons platforms in areas that are inconvenient to get to, making it harder to neutralize the defenders shooting from them.

Admiral Squish
2008-01-06, 04:22 PM
I like the shield idea proposed, personally. Make it of adamantium, three rods, top, middle, and bottom, and let your foes break their weapons against it. Make a reflex save to see if you make it, give a bonus on two-handed weapons ad charges, and watch the shards of weaponry fly.

Another idea: make it into a warforged component!

Gwyn chan 'r Gwyll
2008-01-06, 05:45 PM
Using to reduce recoil would not work. It wouldn't move backwards, but the recoil force is there non-the-less, and it would rip the seige machine apart.

FlyMolo
2008-01-06, 05:57 PM
The idea of archery platforms stands, though. Use a couple immovable rods or a ladder to walk out to a platform constructed in midair. Use it to cover all those angles that towers are so inconvenient for. Best of all, use em as brakes. Activate the rods on a moving object, instant 8000-pound force on the thing holding them. That'll persist until the object stops moving.

OOH! Idea! Flying ships, right? they have a fly speed of clumsy, right? Fire a ballista bolt into the enemy ship, activate the immovability, bring it to a stop. Then when the magic runs out, the ship falls out of the air.

Admiral Squish
2008-01-06, 06:20 PM
Also: Best thief tool ever. Small room, cornered, guard coming in? Jump up, hit the button, pull up, and you can stand over the door, out of sight. Before you drop down and ruin him, that is. Also, bar a door. Get to those hard-to-reach shelves. Pin a guard to the wall by the neck, hit button, back off and move on. Jump check? Who needs? I have an immovable rod. That's practically a fly speed with maneuverability: perfect.

Epic_Wizard
2008-01-06, 09:40 PM
Using to reduce recoil would not work. It wouldn't move backwards, but the recoil force is there non-the-less, and it would rip the seige machine apart.

No if you sovereign glued the rod to the recoiling parts of the weapon then the rod would simply absorb the shock and because it is effectively part of the object it can't smash into or pull against it to break the object. The the real problem is that in medieval weapons any part that "recoils" probably needs to move for the weapon to work. For example a ballista with the cross arms stuck in space can't even fire because those need to move because their movement is what launches the bolt. In modern weapons the recoil is what allows for semi automatic weapons and in artillery if the moving bits don't then the piece has a tendency to explode...


Also: Best thief tool ever. Small room, cornered, guard coming in? Jump up, hit the button, pull up, and you can stand over the door, out of sight. Before you drop down and ruin him, that is. Also, bar a door. Get to those hard-to-reach shelves. Pin a guard to the wall by the neck, hit button, back off and move on. Jump check? Who needs? I have an immovable rod. That's practically a fly speed with maneuverability: perfect.

Yes a fly speed... give or take a Strength check every time you move (assuming you meant two immovable rods) and a dexterity check (if you only meant one).

Besides items that grant flight are fairly inexpensive.

Also as for sticking a guard to the wall... it's button activated... he's going to hit the button and then club you with the rod :smallamused:

serpent615
2008-01-07, 09:59 PM
Also: Best thief tool ever. Small room, cornered, guard coming in? Jump up, hit the button, pull up, and you can stand over the door, out of sight. Before you drop down and ruin him, that is. Also, bar a door. Get to those hard-to-reach shelves. Pin a guard to the wall by the neck, hit button, back off and move on. Jump check? Who needs? I have an immovable rod. That's practically a fly speed with maneuverability: perfect.

Am I missing something with this fly speed thing?...Because it makes no sense to me...:smallconfused:

Admiral Squish
2008-01-07, 10:22 PM
Am I missing something with this fly speed thing?...Because it makes no sense to me...:smallconfused:

Two rods: Set one, release the other, then set the other again, nearer to where you ant to go. Repeat.

serpent615
2008-01-07, 10:49 PM
Two rods: Set one, release the other, then set the other again, nearer to where you ant to go. Repeat.

well, as much as that qualifies as mobility, it is neither practical or easy with the number of balance checks and probably a fort save to not become exhausted.

I was wondering if there was some simpler way I was just oblivious too.

Gawain
2008-01-07, 11:49 PM
My character just got a pair of them recently but I haven't had too much chance to use them yet. I was going to use them to... extract information from a fellow who had infiltrated and attacked us. We were on a ship, and had him in the brig. My intention was to push him up against the rear bars of the cell, hold his hand against the bars, hold the rod against his hand and... click. The forward motion of the ship would certainly move the rod, but the bars should hold for a few seconds, long enough to crush the bones. Then move on to other pressure points, repeat as necessary. Wound up being unnecessary though, for which I was relieved. A little too dark for me.

Other thoughts:
Never mind clotheslining -- get a guy chasing you in a dark alley, forest, etc., and surreptitiously slip the rod behind you and activate it (or if it isn't dark, go ahead and make the rod invisible if you can). Let the guy hit it end-on at a full run and I don't care where he catches it, he's going to be in a world of hurt. Bonus points if the DM lets you sharpen the end without destroying the magic.

We keep some stuff in a magical, virtually unbreakable chest, which can't be opened by normal (including standard magical) means. But it could be absconded with, so when we aren't around to watch it I leave a rod activated inside it.

While onboard the ship I gave one of the rods to our heavily armored dwarf with instructions to activate and hang on for dear life if he ever gets tossed overboard.

Plus, you're never without a coat rack, or a hitching post for your steed. :smallsmile:

SolkaTruesilver
2008-01-08, 12:48 AM
Maybe, but even if it did, it would slow the ship down. A lot.

I'd say it would poke a small hole in the galleon's hull, nothing more.

If, however, you sorround a moored vessel with 5-6 rods, you effectively made it impossible to move until someone figure it out. No inertial means no strenght check. And 5-6 rods together ought to increase the Str DC

serpent615
2008-01-10, 09:19 PM
i gues you can call this a bump, but i coudn't leve my thred at 99 posts...lol

also, anyone know the hardness on wood? becouse that's what's going to realy be important if you use it on say a boat.

Funkyodor
2008-01-11, 02:50 AM
Attach it to a crossbow and you have an instant trap/alarm. String to trigger, string to door, Screaming bolt in crossbow, point at door from some wierd angle (possibly above door somewhere), click immovable rod button.

Talic
2008-01-11, 03:33 AM
I want to see a rod of inertial conservation.

It keeps going at whatever speed it was moving when you push the button, and requires a DC30 Strength check to STOP it.

I can see it now. Tie one end of a rope to it. Tie the other end to someone's pants. Throw up, pressing button on release.

Everything's better when someone's hoisted by their pants.

Naleh
2008-01-11, 04:04 AM
i gues you can call this a bump, but i coudn't leve my thred at 99 posts...lol

also, anyone know the hardness on wood? becouse that's what's going to realy be important if you use it on say a boat.

There are stats at http://www.d20srd.org/srd/dungeons.htm...


Wood wall
typical thickness 6 in.
Break DC 20
Hardness 5
60 hp
Climb DC 21

Destro_Yersul
2008-01-11, 04:12 AM
Also - Immovable Spiked Chain - put it inside someone, and Immobalise it, and the victim cannot move (much).

The immovable torture device. Spiked chain, immovable rod on each end. Wrap around disabled prisoner and activate. Presto, if they move it hurts a LOT. Now dump honey on them and summon a swarm of dire ants.

JimmyDPawn
2008-01-11, 02:58 PM
Personally, if I had to make a cursed version of the immovable rod, I'd make it so when they pushed the button, THEY'D be stuck immobile.

Want to push the button again? Make a DC 30 strength check please.

Snadgeros
2008-01-11, 03:06 PM
No, the best cursed version is the TRULY immovable rod. It's immovable in relation to the universe. You press the button and WHOOSH! Off it flies into outer space, as the Earth and our galaxy hurtle away from it. Roll 3d8, one for each axis of movement, to determine which way it goes. Anyone in the way of it has to make a DC 30 reflex save or take 1d6 damage from it and be knocked prone.

Signmaker
2008-01-11, 03:41 PM
No, the best cursed version is the TRULY immovable rod. It's immovable in relation to the universe. You press the button and WHOOSH! Off it flies into outer space, as the Earth and our galaxy hurtle away from it. Roll 3d8, one for each axis of movement, to determine which way it goes. Anyone in the way of it has to make a DC 30 reflex save or take 1d6 damage from it and be knocked prone.


You know...
Considering how fast we move around the sun ALONE, not factoring in galaxy movement, etc...

I'd think it be a wee bit more than 1d6 damage.

Artanis
2008-01-11, 04:10 PM
Or one that, when you push the button, makes a beeline straight for the nearest Paladin's...uh...well, you get the point :smallwink:

Epic_Wizard
2008-01-12, 10:10 PM
Or one that, when you push the button, makes a beeline straight for the nearest Paladin's...uh...well, you get the point :smallwink:

I do not support paladin stereotyping like this... I do however support any version that goes for Miko's (:miko:) self-righteous "..." where ever in the afterlife it happens to be.

FlyMolo
2008-01-12, 11:33 PM
I do not support paladin stereotyping like this... I do however support any version that goes for Miko's (:miko:) self-righteous "..." where ever in the afterlife it happens to be.
That's hilarious. It would just bob in the air for a second, before taking off on a whirlwind tour of the outer planes. Push the button when you want to get off! Or wait till it finds a paladin.

Patashu
2008-01-12, 11:43 PM
If you are going to be replacing bones and such... just replace them with adamantine, having really hard bones should be at least if not more useful than having immovable ones.


Immovable -adamantine- rods. Best of both worlds!

Patashu
2008-01-13, 12:05 AM
Also, this thread has reminded me of how cool physics-defying objects are. Negative gravitational weight (moves the wrong way in a gravitational field AND/OR exerts gravity in the wrong direction) and negative inertial weight (moves the wrong way when a force is applied on it) would be very exploitable properties, for instance.

Lord_Asmodeus
2008-01-13, 12:09 AM
This thread reminds me of Depths of Madness, when Liet got his hands on an immovable rod and accidentally activated it, and an abiel smashed into it. I think it would make for an AWESOME door-bar. unless it can be broken, but even then it would be awesome.

serpent615
2008-01-13, 12:53 AM
Also, this thread has reminded me of how cool physics-defying objects are. Negative gravitational weight (moves the wrong way in a gravitational field AND/OR exerts gravity in the wrong direction) and negative inertial weight (moves the wrong way when a force is applied on it) would be very exploitable properties, for instance.

that would be interesting...exept for the force one, cus it wouls just be pushing back on what's pushing it...

reminds me of the time i had a fight in an anti-gravity zone....i was on a Monk and slow-fell UP the wall to attack the guy on the celing

KeithTheThinker
2008-01-13, 01:48 AM
I want to see a rod of inertial conservation.

It keeps going at whatever speed it was moving when you push the button, and requires a DC30 Strength check to STOP it.
I was totally thinking of this from the start of reading this thread.

Awesome part? One would usually hold the rod in place before pressing the button, so it seems like an Immovable Rod until they try it again in that high risk Oh-dear-God-in-heaven-stop-me-now situation just after falling off a cliff, and instead the rod just helps to ram them into the ground.

Tie a net between two or more of them, and throw them on either side of your enemy. Bad guy gets caught in the net, and the Rods pull him backwards until he finds himself pinned to the wall by the net.

Thamir
2008-01-13, 03:05 AM
I used teleport any object to put it into the villain's digestive tract and then activated it using mage hand. The villain could not move for fear of being ripped apart. The fighter bull rushed him!!! I think you can guess what happened!

Malachite
2008-01-13, 12:02 PM
I'm so stealing the Rod of Inertial Conservation. :smallbiggrin:

I think the best thing I've seen was someone shoving a rod behind an enemies breatplate and activating it to hold him in place - pretty tame really. Then again I've only had the one turn up in a game, so we haven't had much of an opportunity to be creative with one.

FlyMolo
2008-01-13, 12:56 PM
Also, this thread has reminded me of how cool physics-defying objects are. Negative gravitational weight (moves the wrong way in a gravitational field AND/OR exerts gravity in the wrong direction) and negative inertial weight (moves the wrong way when a force is applied on it) would be very exploitable properties, for instance.

An immovable rod has negative inertial weight. If you pushed on it, it would push right back at you with the same force, and wouldn't move. Negative mass things would be fun, though. I'm having an idea for a bossfight where gravity in the arena isn't constant. Hell yes that would be cool. BBEG jumping around, flying across the arena and flipping switches to drop the PCs upwards? fun. Slippers of spider climb would be really handy.

kieza
2008-01-13, 03:14 PM
Better yet: make the rod of inertial conservation the "unstoppable rod," and make the rod of inertial conservation paired with either it or the immovable rod: whenever you exert a force on the paired rod, it affects the rod of inertial conservation.

I can see it now: activate the immovable rod, and push on it to move the rod of inertial conservation. Instant robotic arm.

Unpleasant Mule
2008-01-13, 04:22 PM
Immovable Rod of Weight.

Every thing's okay, until they try to actually move it. At which point the rod's weight is active, crushing anything under it with 1000lbs of weight.

If someone is holding the rod, it is as though they are now carrying a Stone of Weight with the difference being that once the rod is attuned to them, regardless of whether or not it is immobile, it keeps this effect.

There by making the choices either:

a. Carry around a 1000lb rod.

b. DC30 Str check to move at 10ft a round with an immovable rod.

The effect of 'weight' can be removed in the same manner as removing a Stone of Weight.


Pair this with the Negative Gravitational Weight or the Random Anchor-point for interesting effects.

Patashu
2008-01-13, 08:58 PM
that would be interesting...exept for the force one, cus it wouls just be pushing back on what's pushing it...
Yep, that's the idea.
Imagine all the pranks you could make on people with an orb of that stuff!

Patashu
2008-01-13, 09:03 PM
An immovable rod has negative inertial weight. If you pushed on it, it would push right back at you with the same force, and wouldn't move.
Ah, you're right. I was thinking more along the lines of something that pushed at you more then you pushed at it. So if you pushed it it would pull back, if you pulled it it would drag you away, if you try to pick it up it stays firmly rooted to the ground; you have to push it down instead and it'll come up for you.

EDIT: Actually, no, an immovable rod doesn't have negative inertial weight. Think about it; a sufficiently large wall will accomplish the same thing as an immovable rod, and that doesn't have negative inertial weight. Negative inertial weight means you go the wrong way when a force is applied, not go the wrong way at all. What an immovable rod has is really, really high inertial weight (and an uncanny ability to ignore gravity)

shadow_archmagi
2008-01-13, 09:22 PM
So, does it HAVE to be a rod? What about, say, an immovable brick? Or an immovable boat... or an immovable sandwich...

KeithTheThinker
2008-01-13, 09:42 PM
So, does it HAVE to be a rod? What about, say, an immovable brick? Or an immovable boat... or an immovable sandwich...
Doesn't the real world already have immovable quarters stuck to the sidewalk?

LibraryOgre
2008-01-13, 11:18 PM
So, does it HAVE to be a rod? What about, say, an immovable brick? Or an immovable boat... or an immovable sandwich...

Which is why I prefer working magic items based off their activation type, rather than their shape. I worked out something (http://rpg-crank.livejournal.com/14970.html), which is apparently similar to what is done in Arcana Evolved.

Callos_DeTerran
2008-01-14, 02:05 AM
Dunno if anyone has brought this use up then..and it's mostly for BBEG. Take immovable rod. Smear with Sovereign Glue, leave at about head/neck height in middle of hallway....turn the rod invisible.


Inform the poor sap stuck to the rod that you won't kill him...you just want to play a game...how much do they value whatever is stuck to the rod and how painful do they think dehydration and starvation are? Diabolical laughter then ensues.

KeithTheThinker
2008-01-14, 06:32 AM
Alter the rotation of the planet. Acquire thousands (or millions for faster results) of immovable rods and stick them in the air with each pointing in a north-south direction. Have everybody stand on either the east or west sides, depending on if you want the day to be longer or shorter, of a rod, and have everyone pull at once.

Save yourself from quicksand. Activate it so you can't sink any further, wait to be found.

If you're a prankster, stick on in somebody's backpack before they ride a horse. The jostling is sure to activate it, and then the horse trots off, leaving your victim suspended in midair.

Renx
2008-01-14, 09:16 AM
Dunno if anyone has brought this use up then..and it's mostly for BBEG. Take immovable rod. Smear with Sovereign Glue, leave at about head/neck height in middle of hallway....turn the rod invisible.

Inform the poor sap stuck to the rod that you won't kill him...you just want to play a game...how much do they value whatever is stuck to the rod and how painful do they think dehydration and starvation are? Diabolical laughter then ensues.

DM: "He pushes the button on the rod as a free action and casts a spell. Will saves, everyone"
Dwarf: "Who came up with this, anyway?"


Alter the rotation of the planet. Acquire thousands (or millions for faster results) of immovable rods and stick them in the air with each pointing in a north-south direction. Have everybody stand on either the east or west sides, depending on if you want the day to be longer or shorter, of a rod, and have everyone pull at once.

No one ever said that the Prime Material is a planet :biggrin:


Save yourself from quicksand. Activate it so you can't sink any further, wait to be found.

Or until you can't hold on any longer and sink ;)


If you're a prankster, stick on in somebody's backpack before they ride a horse. The jostling is sure to activate it, and then the horse trots off, leaving your victim suspended in midair.

Or, alternately, the rod rips through the backpack, taking all kinds of valuable stuff with him. Delightful in the middle of a big city. Actually, I'd rule that this doesn't work. If it did, you'd have self-activating immovable rods whenever you start running (and the rod isn't in an extradimensional space).

Kiroho
2008-01-14, 11:04 PM
I rather enjoyed the homebrewed Immovable Arrow.


If this (http://www.giantitp.com/forums/showthread.php?t=46826) is what you were referring to, thank you very much. I rather enjoyed making it.

Chronos
2008-01-15, 12:09 AM
that would be interesting...exept for the force one, cus it wouls just be pushing back on what's pushing it...Everything in the Universe pushes back on what's pushing it, with exactly the same amount of force. That's Newton's Third Law. An object with negative inertial mass would be much, much more interesting than that. If you had a ball of negative-mass stuff, and poked it with a stick, the ball would move towards the stick. This would, of course, cause the contact force to increase, and would cause a normal object to stop again. But the increased force will just cause our hypothetical negasphere to accelerate even more, and move into the stick that much faster. Meanwhile, the force the negasphere is exerting on the stick is also increasing, causing the stick to accelerate in the same direction as the sphere. If the stick has less mass than the absolute value of the sphere, it'd just recoil violently, with the sphere following slowly. But if the stick is more massive, then both will take off through the Universe, perpetually accelerating at an ever-increasing rate as they're pushed tighter and tighter together. And if you think that's weird, don't even get me started on what happens if you have a negative-mass particle which also has an electric charge.

sikyon
2008-01-15, 12:26 AM
Nitpick:

Inertial conservation is a poor name for a rod which just keeps going. That's more like the opposite of inertial conservation. So the Inertial Rod would be more apt :smalltongue:

Epic_Wizard
2008-01-15, 10:38 AM
I was totally thinking of this from the start of reading this thread.

Awesome part? One would usually hold the rod in place before pressing the button, so it seems like an Immovable Rod until they try it again in that high risk Oh-dear-God-in-heaven-stop-me-now situation just after falling off a cliff, and instead the rod just helps to ram them into the ground.

Actually I would simply flail the arm holding the rod upwards and thus slow my fall since when the rod is activated it is not moving down as fast as I am. Get two of these and you can effectively reverse any fall.

What would happen if one went into a Bag of Holding or similar space while active (and moving)?


Everything in the Universe pushes back on what's pushing it, with exactly the same amount of force. That's Newton's Third Law. An object with negative inertial mass would be much, much more interesting than that. If you had a ball of negative-mass stuff, and poked it with a stick, the ball would move towards the stick. This would, of course, cause the contact force to increase, and would cause a normal object to stop again. But the increased force will just cause our hypothetical negasphere to accelerate even more, and move into the stick that much faster. Meanwhile, the force the negasphere is exerting on the stick is also increasing, causing the stick to accelerate in the same direction as the sphere. If the stick has less mass than the absolute value of the sphere, it'd just recoil violently, with the sphere following slowly. But if the stick is more massive, then both will take off through the Universe, perpetually accelerating at an ever-increasing rate as they're pushed tighter and tighter together. And if you think that's weird, don't even get me started on what happens if you have a negative-mass particle which also has an electric charge.

But wouldn't the 'negasphere exert a force on the stick that is opposite to the force that a normal object would exert? Thus you would not have an infinitely moving system you would have an infinitely collapsing system which would either 'break' both objects or create a Neutronium shell on the 'negasphere' as even air was drawn into the object and then stripped down into its component molecules which would mush into Neutronium. Since this would probably release a level of radiation that would flash fry anything without several million miles and at least one atmosphere or other radiations shield between them and it AND it would be triggered by contact with the air I would recommend against this.

This doesn't even take into account what the gravitational effects of the Neutronium would be. For all I know this could generate a Neutron Star.

(though if you could get a RBBEG next to the reaction it would solve a lot of problems)

Chronos
2008-01-15, 01:38 PM
But wouldn't the 'negasphere exert a force on the stick that is opposite to the force that a normal object would exert?No. The force of A on B must be in the opposite direction from the force of B on A, regardless of what A and B are. The sphere's negative mass doesn't change any of the forces involved; it just changes the effects of those forces on the negasphere.

KeithTheThinker
2008-01-15, 05:30 PM
Actually I would simply flail the arm holding the rod upwards and thus slow my fall since when the rod is activated it is not moving down as fast as I am. Get two of these and you can effectively reverse any fall.

But would you do that with an immovable rod? I meant that someone would supposedly be holding the rod relatively still when activating it anywhere, so as to place it precisely. If no one knows that their rod is one of inertial conservation rather than immovability, one would have no reason to flail.

Epic_Wizard
2008-01-17, 08:42 AM
No. The force of A on B must be in the opposite direction from the force of B on A, regardless of what A and B are. The sphere's negative mass doesn't change any of the forces involved; it just changes the effects of those forces on the negasphere.

If it has negative mass then all of the force vectors would be reversed with respect to the negasphere meaning that it would also apply negative force as well as receive it. I don't have time right now but if we really wanted to see how the interactions should work then work out the free body diagram for the negasphere and a regular object of equal mass with the normal object moving at the negasphere at a slow speed. Then replace the regular object with another negasphere and the interaction should then be the same as two normal objects. If it doesn't then we know that there is an error in the math of the original interaction between the normal object and the negasphere.


But would you do that with an immovable rod? I meant that someone would supposedly be holding the rod relatively still when activating it anywhere, so as to place it precisely. If no one knows that their rod is one of inertial conservation rather than immovability, one would have no reason to flail.

This assumes that the person already knows what the rod is. Besides even if they didn't I would think that since it operates independently of gravity it would at least maintain their speed at the time the pushed the button which could considerable reduce their falling damage.

Chronos
2008-01-17, 10:33 PM
If it has negative mass then all of the force vectors would be reversed with respect to the negasphere meaning that it would also apply negative force as well as receive it.No, the forces would all be the same (except possibly for gravitational forces, but we appear to be distinguishing between inertial mass and gravitational mass, here), since the forces are generated in the same ways as normal. What would be reversed, thanks to F = ma, would be the accelerations. And two negative-mass objects would not interact in the same way as two positive-mass objects, unless there were also some change in the way the forces worked.

Epic_Wizard
2008-01-20, 03:58 PM
No, the forces would all be the same (except possibly for gravitational forces, but we appear to be distinguishing between inertial mass and gravitational mass, here), since the forces are generated in the same ways as normal. What would be reversed, thanks to F = ma, would be the accelerations. And two negative-mass objects would not interact in the same way as two positive-mass objects, unless there were also some change in the way the forces worked.

But what about Newton's Third Law of Motion? Since the negasphere is also applying a force on the object wouldn't that force be in the opposite direction that we would expect? Or rather it's effect would be. This is what would cause the object to compress into the negasphere.

serpent615
2008-01-20, 08:51 PM
But what about Newton's Third Law of Motion? Since the negasphere is also applying a force on the object wouldn't that force be in the opposite direction that we would expect? Or rather it's effect would be. This is what would cause the object to compress into the negasphere.

To think this thread passed from Immovable Rods, and into the advance theoretical Physics genre.

Chronos
2008-01-20, 11:23 PM
But what about Newton's Third Law of Motion? Since the negasphere is also applying a force on the object wouldn't that force be in the opposite direction that we would expect? Or rather it's effect would be. This is what would cause the object to compress into the negasphere.Yes, the negasphere is exerting a force on the normal object, but since it's a force on the normal object, we use the mass of the normal object to determine the force's effect.

To illustrate: Suppose that we have a negasphere of mass -1 kg, pressing up against a normal object of mass +1 kg, thus:

----++++
----++++
----++++
----++++

Since they're pressed together, there's a force between them. Let's say the force of the normal object on the negasphere is 1 Newton to the left. By Newton's 3rd, then, the force of the negasphere on the normal object is 1 Newton to the right.

Now we look at the masses, and use Newton's 2nd to determine the accelerations. The negasphere has a force on it of 1 N left, and a mass of -1 kg, so the negasphere will have an acceleration of 1 m/s2 to the right. Meanwhile, the normal object has a force on it of 1 N right, and a mass of 1 kg, so it'll have an acceleration of 1 m/s2 right, also. So both objects zip off together to the right, at an ever-increasing speed.


To think this thread passed from Immovable Rods, and into the advance theoretical Physics genre.The transition isn't all that surprising: physicists love neat toys like Immovable Rods. But this isn't anywhere near advanced theoretical physics: Every high school student (and advanced middle-schoolers) should learn Newton's Laws.

krossbow
2008-01-21, 01:28 AM
If as a DM you ever want the area to begin to crumble under the strain of battle, but don't want to explain where all that rock is going, having the castle be mostly hollow with immovable rods as supports.

Jack Zander
2008-01-21, 01:44 AM
...poor, helpless catgirls...

daggaz
2008-01-21, 03:58 AM
No, the forces would all be the same (except possibly for gravitational forces, but we appear to be distinguishing between inertial mass and gravitational mass, here), since the forces are generated in the same ways as normal. What would be reversed, thanks to F = ma, would be the accelerations. And two negative-mass objects would not interact in the same way as two positive-mass objects, unless there were also some change in the way the forces worked.

Dude... you are usually better at math than this.

F = m*a

If m = -m (negative mass) then

F = -m*a which is the opposite of the original equation, or in other words, F = -F, so yeah, the resultant force vector is opposite as well. And because the force vector is opposite, so is the acceleration. (it is, after all, the force field(s) which generates the acceleration by working on the mass(es).

Yes the forces are generated in the same way as normal, but the resultant vector is the opposite (push instead of pull).

Of course, this is a dangerous way to look at this equation, because we are talking about two interacting bodies here (ignoring the earth for the moment), and thus should really be using

g=G*m_1*m_2/r^2

Which while being more accurate and taking into account both masses and the universal constant of gravitational force between them, it returns the same negative value of resultant force if one of the masses is negative. In this case, as before, the negative sign means a pushing force, rather than a pulling force. Note that if two negative masses approach eachother, they once again attract eachother, rather than repel. This is your proof that the fundamental mechanic behind the generation of force is unchanged, and that it is only the direction of the resultant field which is reversed in the case of negative mass.

daggaz
2008-01-21, 06:34 AM
Everything in the Universe pushes back on what's pushing it, with exactly the same amount of force. That's Newton's Third Law. An object with negative inertial mass would be much, much more interesting than that. If you had a ball of negative-mass stuff, and poked it with a stick, the ball would move towards the stick. This would, of course, cause the contact force to increase, and would cause a normal object to stop again. But the increased force will just cause our hypothetical negasphere to accelerate even more, and move into the stick that much faster. Meanwhile, the force the negasphere is exerting on the stick is also increasing, causing the stick to accelerate in the same direction as the sphere. If the stick has less mass than the absolute value of the sphere, it'd just recoil violently, with the sphere following slowly. But if the stick is more massive, then both will take off through the Universe, perpetually accelerating at an ever-increasing rate as they're pushed tighter and tighter together. And if you think that's weird, don't even get me started on what happens if you have a negative-mass particle which also has an electric charge.

Ok...and now you are just way off.

First: poking something with a stick.. .this 'contact' force you speak of is the electromagnetic force. That's right, everytime you touch something, or walk on the ground, you aren't really physcially touching it at all. The electrons in your atoms are forcing the electrons in the other atoms away from you. Just like magnets, eh? The electromagnetic force is independant of mass, so unless our hypothetical "nego-sphere" is also entirely reversely charged (not at all strange in our universe, its called anti-matter), we get absolutely no difference there.

Second...why would the ball move towards the stick? Normal mass (the stick) attracts other normal mass. If the ball is negative mass, the stick should repel it, unless the stick is also made of negative matter.. then you get attraction again. This by the way is independant of the electromagnetic force between the objects, so ignore that you touch it with the stick for now, and just assume you hold them close to see what happens.

Third.. If it has negative mass, then it will have negative momentum, as well. This is bad for the universe, and doesn't work. Thats why there is no such thing as negative mass. Basically this would lead to an immediate break down of Newton's first law and the conservation of energy. Yes, the negasphere would assist, rather than resist, any efforts to push it away, but the stick wouldn't follow it, and it would be quickly hard pressed to keep up as well. (but colliding particles, say a gas cloud of negaparticles, would increase in energy (temperature!) automatically until the gas completely dispersed, thus the break down in physics.)


So. If we push a negasphere with a normal stick, we observe two forces at work.

First, the negasphere has a tiny reaction to the gravitational force of the stick (its tiny, almost not measurable) which is opposite the normal effect and actually pushes the negasphere away, slightly.

This causes a slight increase in the velocity of the negasphere, but the acceleration dies down rather quickly as the negasphere moves away from the stick and the field dies down exponentially. At some point, it would reach an equilibrium state except for one thing...

Force number two. We push it with the stick. The electromagnetic force pushes at over 10,000 times the effective force of gravity, so the negasphere really gets going. Still, the force is only applied over a small amount of time, and the integral is finite, so the total amount of acceleration is finite as well, and the sphere simply moves away from us REGARDLESS of the relative mass of the stick. (by the way, the sticks mass compared to the absolute value of the sphere? wth??) Interestingly, it isnt infinite energy as stated above, but is infact easily defined. We get exactly the same amount of energy put into the velocity for the negasphere, as is usually taken out when moving an identical sphere of normal mass. Its a well defined amount. So the negasphere just moves away from us faster than a normal sphere would.

That is, until it collides with something else, in which case it rebounds with increased energy, and then it bounces again, this time even faster! and faster! and faster!!... and now we have invented flubber. You get the point.

Watch the whole disney series of Flubber movies for more fascinating physics with negative mass (yes, they invent a flying car).

Chronos
2008-01-21, 02:12 PM
F = -m*a which is the opposite of the original equation, or in other words, F = -F, so yeah, the resultant force vector is opposite as well. And because the force vector is opposite, so is the acceleration. (it is, after all, the force field(s) which generates the acceleration by working on the mass(es).You're reading that equation backwards. The acceleration doesn't cause the force; the force causes the acceleration. Something else (usually electromagnetic effects, as you say) causes the force, and the mass being negative won't have any effect on how electromagnetism works.

Second...why would the ball move towards the stick? Normal mass (the stick) attracts other normal mass. If the ball is negative mass, the stick should repel it, unless the stick is also made of negative matter.. then you get attraction again.When you say "normal mass attracts other normal mass", you're referring to gravity. But the gravitational force between two handheld objects is neglible compared to the electromagnetic force between them, so I was completely ignoring it. The dominant force here is a contact force (which, yes, is electromagnetic), which will tend to push the objects apart if they're pressed together. So the stick does indeed repel the negasphere, in the sense that the force of the stick on the sphere is pointed away from the stick. But a force in the "away" direction, acting on a negative mass object, will cause an acceleration in the "towards" direction.

Corinthus
2008-01-21, 06:02 PM
Yeah, Chronos has got it right here. Interestingly, his example also follows the law of conservation of momentum. (since p=mv). Any other weird things this thread can come up with?

serpent615
2008-01-21, 06:38 PM
The transition isn't all that surprising: physicists love neat toys like Immovable Rods. But this isn't anywhere near advanced theoretical physics: Every high school student (and advanced middle-schoolers) should learn Newton's Laws.

I meant the negasphere idea, not the laws...those are beyond simple physics. that an object can have negative weight will create a force in a negative direction IS beyond standard physics though. And personally, I drought you can really apply Nekton’s laws to this at all, since by the third law, the force one way MUST be in tot opposite direction. You broke that in your own explanation.


Yeah, Chronos has got it right here. Interestingly, his example also follows the law of conservation of momentum. (since p=mv). Any other weird things this thread can come up with?

as for that, i'm out of ideas... anyone else?

Doomsy
2008-01-21, 07:01 PM
Put it in the middle of Limbo, activated. Take that, ever changing reality-soup!

Doomsy
2008-01-21, 07:16 PM
Put it in the middle of Limbo, activated. Take that, ever changing reality-soup!

serpent615
2008-01-21, 07:33 PM
there a specific reason you posted that twice?

Chronos
2008-01-21, 11:23 PM
And personally, I drought you can really apply Nekton’s laws to this at all, since by the third law, the force one way MUST be in tot opposite direction. You broke that in your own explanation.Did I? Where? I'm pretty sure that in all of my explanations, I kept the forces in opposite directions. The accelerations, though, are not necessarily in opposite directions.

And as weird as it is to apply Newton's laws to a negative-mass object, it actually gets even weirder if they don't apply. Take my word on this.

serpent615
2008-01-22, 11:00 AM
Did I? Where? I'm pretty sure that in all of my explanations, I kept the forces in opposite directions. The accelerations, though, are not necessarily in opposite directions.

And as weird as it is to apply Newton's laws to a negative-mass object, it actually gets even weirder if they don't apply. Take my word on this.

looking back, you did...I guess...although this is all theoretical stuff anyways.

I mean, have you ever seen anything with negative weight?

Chronos
2008-01-22, 01:29 PM
I mean, have you ever seen anything with negative weight?No, and it's a darn shame. I never get any of the cool toys.

Godna
2008-01-22, 07:25 PM
Can we get this back to potential uses of the Immovable rod?

serpent615
2008-01-22, 07:34 PM
Can we get this back to potential uses of the Immovable rod?

I agree...I’ll get us going....the ultimate paper weight, for those REALY windy days.

Epic_Wizard
2008-02-05, 09:27 AM
Use them in a bluff attempt while fighting. You punch at your enemy's head and activate the Rod before you hit. Then use the rod as a pivot to transfer your momentum into kicking him in the gut or other anatomy :smallbiggrin:

serpent615
2008-02-05, 03:42 PM
Use them in a bluff attempt while fighting. You punch at your enemy's head and activate the Rod before you hit. Then use the rod as a pivot to transfer your momentum into kicking him in the gut or other anatomy :smallbiggrin:

that would work if D&D actualy had combat like that...o well:smallsigh: