Reverse Gravity?

[Galvin]

Hi GITP

I read the description of the Reverse Gravity spell and was a bit confused.


This spell reverses gravity in an area, causing all unattached objects and creatures within that area to fall upward and reach the top of the area in 1 round

So by RAW, the Reverse Gravity spell cast outside makes creatures fly up and up and up, until they slam into some space object, in the standard 6 second round. (Of course, you may consider the atmosphere a barrier, though that's up to the DM.)

Is this correct? Am I interpreting it correctly?

[Jormengand]

Hi GITP

I read the description of the Reverse Gravity spell and was a bit confused.



So by RAW, the Reverse Gravity spell cast outside makes creatures fly up and up and up, until they slam into some space object, in the standard 6 second round. (Of course, you may consider the atmosphere a barrier, though that's up to the DM.)

Is this correct? Am I interpreting it correctly?

No, unless your "Area: Up to one 10-ft. cube per two levels" is up to reaching space. "The area" is the area of the spell.


If an object or creature reaches the top of the area without striking anything, it remains there, oscillating slightly, until the spell ends. At the end of the spell duration, affected objects and creatures fall downward.

[Psyren]

"The area" refers to the area of the spell, not the physical area you cast it in. If you cast it outside, it will take affected creatures to the top of the highest 10ft. cube you placed above them.

[Galvin]

Ah, yes, that make more sense. Thank you.

[Hamste]

Someone should optimize a character specifically to make reverse gravity get the target up to space.

[Psyren]

Someone should optimize a character specifically to make reverse gravity get the target up to space.

At 5ft./level you're going to need an epic CL to do that anyway, so you might as well just use Nailed to the Sky. (http://www.d20srd.org/srd/epic/spells/nailedToTheSky.htm)

[Invader]

I'd have to put reverse gravity on the list of seriously overrated spells.

[Psyren]

I'd have to put reverse gravity on the list of seriously overrated spells.

It's AoE no save*, no SR, just suck - I don't see what's so bad about that. Just about any monster without a flight speed or ranged attacks can be shut down with this.


*with careful placement

[Invader]

It's AoE no save*, no SR, just suck - I don't see why it's so bad about that. Just about any monster without a flight speed or ranged attacks can be shut down with this.


*with careful placement

I didn't say it was bad but it's def oftentimes overrated.

[Hamste]

At 5ft./level you're going to need an epic CL to do that anyway, so you might as well just use Nailed to the Sky. (http://www.d20srd.org/srd/epic/spells/nailedToTheSky.htm)

Eh, people thought becoming a god at level 5 was impossible until punpun did it...I'm sure there is some combination of spell shaping, area increasing and cl stacking that can do it. I just need to find it...after all it is only 328000 feet straight up.

[Silva Stormrage]

I didn't say it was bad but it's def oftentimes overrated.

I actually don't see how it can be overrated. Its either useless or instantly wins the fight... If the subject has wings or a flight speed than ya it won't work but against anything else it can pretty much instantly win the fight. Sure at that level a lot of things will have flight speed but I could still see it as a really good spell.

[Emperor Tippy]

Someone should optimize a character specifically to make reverse gravity get the target up to space.

Shapechange -> shift to Zodar -> Wish up CL fifty million scroll of Reverse Gravity -> shift to Lilitu -> Item Use Scroll of Reverse Gravity.

Total Cost: 3,825 GP.
Minimum level: 4

Be a 7th level Cosmic Descryer, cast Delay Death, cast Favor of the Martyr, use Cosmic Connection to cast a CL fifty million Reverse Gravity, die, get resurrected with any of the methods that don't result in level loss (or just get hit with an Epic Heal).

It's not that hard.


I'd have to put reverse gravity on the list of seriously overrated spells.

Honestly, I see it more often underrated than I do overrated. There are whole swaths of challenges that it can pretty much negate with just the one spell.

[Psyren]

I actually don't see how it can be overrated. Its either useless or instantly wins the fight... If the subject has wings or a flight speed than ya it won't work but against anything else it can pretty much instantly win the fight. Sure at that level a lot of things will have flight speed but I could still see it as a really good spell.

Indeed - it shuts down almost every ooze, plant, golem and non-air elemental in the game regardless of CR, resistances or immunities. Living Spells blocking the door? Send them up, walk around them. (Or clamber along the "floor" with a climb check.)

[Chronos]

And that's just the combat applications. You can do some seriously cool architectural tricks with it, too, like a floating castle, or a perpetual catapult.

[John Longarrow]

Make two 10'x10' platforms. Link them together with 10' chains at the corners, one over the other.

Cast reverse gravity on the bottom plate.

Top one falls away. Make sure it weighs more than the bottom plate. Chains pull the bottom plate along, pushing the top plate higher.

[Psyren]

Make two 10'x10' platforms. Link them together with 10' chains at the corners, one over the other.

Cast reverse gravity on the bottom plate.

Top one falls away. Make sure it weighs more than the bottom plate. Chains pull the bottom plate along, pushing the top plate higher.

Maybe I'm not visualizing it right, but what would this accomplish, besides squashing anyone standing between the two plates when they reach the top of the spell area?

[nightwyrm]

Maybe I'm not visualizing it right, but what would this accomplish, besides squashing anyone standing between the two plates when they reach the top of the spell area?

I think the gist of the idea (don't know if it'll actually work) is that the bottom plate is the spell area, which is now mobile.

[Segev]

I think he's assuming the area is tied to the plate that's pulling everything upwards, rather than to a space. I don't think that's how the spell's targetting actually works, though.

[Phelix-Mu]

I like casting reverse gravity, then tossing a tree token into the mix. Dismiss. Repeat. Add more tree tokens, and possibly fire, to taste.

Trees and other terrain objects are largely designed to be stable with standard gravity. If you reverse gravity, the root system of a tree or the foundation of a building stand a pretty good chance of failing catastrophically. This can make for some extremely amusing trap-building.

The spell is not overrated, imho. It is one of my favorite spells to richard around with, because the possibilities scale directly with creativity, but aren't always immediately obvious.

[Emperor Tippy]

Maybe I'm not visualizing it right, but what would this accomplish, besides squashing anyone standing between the two plates when they reach the top of the spell area?

It's playing with frames of reference.

It makes the dominant frame of reference for gravity affecting the top plate be the bottom plate. The top plate is "falls" upwards at 1g. Since it masses more it's kinetic energy is more than that of the bottom plate which is falling downwards at 1g. This causes the top plate to pull the whole contraption upwards at a rate of (KE of top plate - KE of bottom plate).

This moves the reverse gravity effect (which is fixed in relation to the bottom plate) upwards, thus pushing the whole contraption ever higher.

It's just one of a large number of fun things you can do if you get to choose what spells are anchored in reference to.

The reason that this doesn't work is because Reverse Gravity just affects cubes of space with no reference frame, it's not "The cube above the floor that I am standing on", it is "This cube right here, that is currently (at the time of casting) above the floor that I am standing on."

[Phelix-Mu]

The reason that this doesn't work is because Reverse Gravity just affects cubes of space with no reference frame, it's not "The cube above the floor that I am standing on", it is "This cube right here, that is currently (at the time of casting) above the floor that I am standing on."

Aw, no perpetual motion machine (as long as the spell lasts). Not that I had considered that use, though. It would be pretty cool if it was as flexible as that.

Still, there are a ton of things you can do with this.

[unseenmage]

Creatures with natural flight are boned by this too. Their flight is based on lift and their ability to flip upside down at will would be largely governed by their maneuverability. (I think.)

Unless I miss my guess creatures with natural winged flight would "fall" out of the sky and get a Reflex save to "right" themselves at the very least.

Nevermind, nothing to see here. Move along.

[Invader]

Creatures with natural flight are boned by so this too. Their fion light is based on lift and their ability to flip upside down at will would be largely governed by their maneuverability. (I think.)

Unless I miss my guess creatures with natural winged flight would "fall" out of the sky and get a Reflex save to "right" themselves at the very least.

It specifically calls out creatures with flight can keep from falling with no distinction about what kind of flight so nothing special would happen.

[Phelix-Mu]

It specifically calls out creatures with flight can keep from falling with no distinction about what kind of flight so nothing special would happen.

Which is why one should combo the spell with loose rocks, debris, water, and/or tree tokens.:smallwink:

[unseenmage]

Which is why one should combo the spell with loose rocks, debris, water, and/or tree tokens.:smallwink:

Or use it to disrupt the Jumplomancer. I think that would work. Or would they just suddenly be jump-hovering upside down as the whole trick just stalls their movement regardless of gravity?

[TuggyNE]

The reason that this doesn't work is because Reverse Gravity just affects cubes of space with no reference frame, it's not "The cube above the floor that I am standing on", it is "This cube right here, that is currently (at the time of casting) above the floor that I am standing on."

Someone is bound to come in and argue strenuously that the orbit of the planet around its star, the star in its galaxy, and galaxy in supercluster force the spell to actually take note of some sort of reference frame. But D&D doesn't really work like that, so Tippy is correct.

[Phelix-Mu]

Someone is bound to come in and argue strenuously that the orbit of the planet around its star, the star in its galaxy, and galaxy in supercluster force the spell to actually take note of some sort of reference frame. But D&D doesn't really work like that, so Tippy is correct.

The only place that frame of reference and it's very badly outlined role in the game becomes relevant is in large, moving vehicles, like ships at sea. Then stuff can get weird.

I've often wondered about the rules for teleporting. If the location that you are teleporting to is mobile, can you still teleport there? What are the limits of this train of thought? Because a ruling either way can start to seem strange if one extrapolates.

[Chronos]

Quoth Emperor Tippy:

It makes the dominant frame of reference for gravity affecting the top plate be the bottom plate. The top plate is "falls" upwards at 1g. Since it masses more it's kinetic energy is more than that of the bottom plate which is falling downwards at 1g. This causes the top plate to pull the whole contraption upwards at a rate of (KE of top plate - KE of bottom plate).

Right idea, but wrong details. Kinetic energy isn't particularly useful or relevant here-- All you need is good ol' F = ma. The top plate has a weight force pulling it up, and the bottom plate has a weight force pulling it down. Net force is equal to the difference of the two weights, acting on a total mass of the sum of the two masses. So the acceleration (not speed) of the whole contraption is equal to g*(mtop - mbottom)/(mtop + mbottom), or g*(1-r)/(1+r), where r is the ratio of masses.

As you said, it doesn't work, because you're not allowed to fix the spell to the reference frame of the bottom plate. It's still quite possible to make a perpetual motion machine from this spell, though. Just put something on the side edge of the spell, so it goes up on the inside, and down on the outside. A large flywheel would work, as would a fountain of water, or boulders rolling along a track. This is how the perpetual catapult I mentioned works.

[unseenmage]

Someone is bound to come in and argue strenuously that the orbit of the planet around its star, the star in its galaxy, and galaxy in supercluster force the spell to actually take note of some sort of reference frame. But D&D doesn't really work like that, so Tippy is correct.

There is a feat, Create Moving Portal (http://www.wizards.com/default.asp?x=dnd/pg/20030611a), that allows Portals to be bound to a relative frame rather than D&D's largely universal one.

It wouldn't be too terribly hard to 'brew up a version for spells as well.

[Psyren]

It's playing with frames of reference.

It makes the dominant frame of reference for gravity affecting the top plate be the bottom plate. The top plate is "falls" upwards at 1g. Since it masses more it's kinetic energy is more than that of the bottom plate which is falling downwards at 1g. This causes the top plate to pull the whole contraption upwards at a rate of (KE of top plate - KE of bottom plate).

This moves the reverse gravity effect (which is fixed in relation to the bottom plate) upwards, thus pushing the whole contraption ever higher.

It's just one of a large number of fun things you can do if you get to choose what spells are anchored in reference to.

The reason that this doesn't work is because Reverse Gravity just affects cubes of space with no reference frame, it's not "The cube above the floor that I am standing on", it is "This cube right here, that is currently (at the time of casting) above the floor that I am standing on."

Ah, I gotcha. I was mentally picturing the fixed frame, and thus both plates hurling up through the spell area to the top of the cube and smashing together when the chains grew slack (squashing anything between them.)

[Phelix-Mu]

It's still quite possible to make a perpetual motion machine from this spell, though. Just put something on the side edge of the spell, so it goes up on the inside, and down on the outside. A large flywheel would work, as would a fountain of water, or boulders rolling along a track. This is how the perpetual catapult I mentioned works.

Ack. See? Genius. The pure awesome of this spell continues to amaze me. Limited duration is not good, but an item with some kind of permanent or renewable effect, resettable magical trap....ack. So many possibilities.

I was so happy when I discovered that this spell was on the druid spell list.

[Segev]

Since traps (thanks, Tippy, for pointing out they are in the SRD) are 500 gp x CL x Spell Level, and you'd just have this one be triggered by the motion of the swinging arm anyway, it'd be 500 x 13 x 7 = 45,500 gp plus some XP to craft a Reverse Gravity trap that was part of this proposed perpetual motion machine.

[Chronos]

Even simpler: Reverse Gravity is also eligible for Permanency.

[Mr Beer]

I remember reading a really old article with a Reverse Gravity trap.

So you have an area trapped with Reverse Gravity. The floor in the area is a large slab of stone lying on, but not attached to, rock below it. The ceiling is another large slab of stone hanging from brittle wooden supports.

So you walk into the area, Reverse Gravity goes off. You fall upwards, with the floor slab close behind. You hit the ceiling and take falling damage. The floor slab squashes you into the ceiling for lots more damage. The pressure breaks the ceiling supports. When the Reverse Gravity ends, you fall back down, taking falling damage and then the ceiling slab hits and squashes you for a 4th set of damage.

[Segev]

Even simpler: Reverse Gravity is also eligible for Permanency.
It is? I don't see it on the list...

[Phelix-Mu]

I remember reading a really old article with a Reverse Gravity trap.

So you have an area trapped with Reverse Gravity. The floor in the area is a large slab of stone lying on, but not attached to, rock below it. The ceiling is another large slab of stone hanging from brittle wooden supports.

So you walk into the area, Reverse Gravity goes off. You fall upwards, with the floor slab close behind. You hit the ceiling and take falling damage. The floor slab squashes you into the ceiling for lots more damage. The pressure breaks the ceiling supports. When the Reverse Gravity ends, you fall back down, taking falling damage and then the ceiling slab hits and squashes you for a 4th set of damage.

Yay. Just like my thing with the tree tokens, but possibly even better. Having multiple enemies charging through what is essentially an invisible field of woopsy-daisy is just priceless, as they fall up one after another and start crushing each other, followed by flaming 60' oak trees. Dismiss, repeat.

I had a character, high-level mind you, pull this off, for a ridiculous amount of damage off of two spell and an obscenely cheap item. Granted it was the warlock that lit the whole party on fire, but my druid was the chief engineer. Took apart a sizable number of extremely beefy enemy bruisers.