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Tyndmyr
2010-07-26, 05:25 PM
I was curious, so I actually went and found an old copy of spelljammer.

There's the usual 20d6 falling damage upon impact of course, but even better, after you've fallen far enough to ensure maximum falling damage, you start taking heat damage. 1d4 the first round. Doubles every round. No cap on this damage, and it notes that fire resist items help, but will be eventually overwhelmed.

Awesome. Clearly, skydiving without a chute is still doable, but a helluva lot more dangerous.

Caphi
2010-07-26, 05:26 PM
Fire elementals should gain temporary HD and size categories.

Snake-Aes
2010-07-26, 05:30 PM
Or dissipate instead. Just let them be immune to the heat =P

Suddenly I think of Star Elf Warblades visiting the world via Atmospheric Reentry.

W3bDragon
2010-07-26, 05:30 PM
1d4 the first round. Doubles every round. No cap on this damage

Does it say how many rounds it would take for reentry from orbit?

Morph Bark
2010-07-26, 05:36 PM
1d4 the first round. Doubles every round. No cap on this damage,

So... considering terminal velocity is 300 feet per round, this heat damage would start after two rounds (first round of falling is just 150 feet since you haven't reached terminal velocity yet). After 10 rounds (3000 feet) you'd take 1024d4 heat damage. After 20 rounds (6000 feet), you'd take (1024^2)d4 heat damage. Re-entry? You don't even need to be out of the lowest layer of atmosphere for this! Just be a little more than a mile high, as long as they don't have fire immunity or feather fall effects. Or teleportation, but does that remove velocity?

Eurus
2010-07-26, 05:37 PM
Now I'm imagining a lich creating a space cannon to launch fire elementals at the planet from orbit. :smallbiggrin:

^EDIT: Yikes. Makes "I teleport him a mile up" much scarier.

Snake-Aes
2010-07-26, 05:38 PM
So... considering terminal velocity is 300 feet per round, this heat damage would start after two rounds (first round of falling is just 150 feet since you haven't reached terminal velocity yet). After 10 rounds (3000 feet) you'd take 1024d4 heat damage. After 20 rounds (6000 feet), you'd take (1024^2)d4 heat damage. Re-entry? You don't even need to be out of the lowest layer of atmosphere for this! Just be a little more than a mile high, as long as they don't have fire immunity or feather fall effects. Or teleportation, but does that remove velocity?

Make it additive instead of multiplicative. ++1d4 per round. It's still going to be obscene anyway.

Morph Bark
2010-07-26, 05:40 PM
Now I'm imagining a lich creating a space cannon to launch fire elementals at the planet from orbit. :smallbiggrin:

^EDIT: Yikes. Makes "I teleport him a mile up" much scarier.

Heh. If I still had my notebooks from 6th grade, I could tell you the amount of d4s necessary for the amount of heat damage inflicted upon someone falling more than 80+ rounds at terminal velocity. :smallamused:

Suffice to say, there aren't enough dice in the world for that. Or at least not enough d4s.

dspeyer
2010-07-27, 12:30 AM
So... considering terminal velocity is 300 feet per round, this heat damage would start after two rounds (first round of falling is just 150 feet since you haven't reached terminal velocity yet). After 10 rounds (3000 feet) you'd take 1024d4 heat damage. After 20 rounds (6000 feet), you'd take (1024^2)d4 heat damage. Re-entry? You don't even need to be out of the lowest layer of atmosphere for this! Just be a little more than a mile high, as long as they don't have fire immunity or feather fall effects. Or teleportation, but does that remove velocity?

Falling from within the atmosphere doesn't cause heat damage. Otherwise there'd be no skydivers.

Heat comes from exceeding terminal velocity by falling through vacuum and rapidly decelerating when you hit the atmosphere.

It's easy to calculate energy-per-height, but a bit harder to calculate hit-points-lost-per-energy-dissipated. There's also the question of whether you slow to terminal velocity before hitting the ground. If so, the usual 20d6 rule applies, and all your excess energy is heat. If not, things get more complicated.

Tyndmyr
2010-07-27, 01:06 AM
As an addendum, if you were in something, you didn't take the damage, the vessel did. You only began taking damage if the vehicle failed.

Awesome visuals commence.

Keep in mind that this is from spelljammer, in which the assumption of earthlike atmosphere, terminal velocity, etc are not taken as standard. You inherently have a certain loss of detail as general rules are used. Amount of atmosphere does vary immensely, though. Im pretty sure you're not really supposed to survive unaided re-entry to earth like planets from orbit, though.

Also, if you have a controlled landing, such as say, a fly spell, damage doesn't apply, and thus, your heat damage starts over. That, a highly fire resistant vessel(or a succession of those) or immunity to fire are likely the best ways to actually pull a skydive from orbit off.

Goonthegoof
2010-07-27, 01:33 AM
Tyndmyr, about the character in your sig- How'd you get wiz1/mspec 3? Don't you need knowledge:arcana and spellcraft to have 5 ranks first?

Morph Bark
2010-07-27, 04:37 AM
Falling from within the atmosphere doesn't cause heat damage. Otherwise there'd be no skydivers.

Heat comes from exceeding terminal velocity by falling through vacuum and rapidly decelerating when you hit the atmosphere.

I know, but what the OP suggested was that it'd start after someone reaches terminal velocity under DnD rules.

KillianHawkeye
2010-07-27, 07:28 AM
Falling from within the atmosphere doesn't cause heat damage. Otherwise there'd be no skydivers.

Heat comes from exceeding terminal velocity by falling through vacuum and rapidly decelerating when you hit the atmosphere.

Terminal velocity is based on the atmosphere you're falling through. There IS no terminal velocity in a vacuum.

Morph Bark
2010-07-27, 09:48 AM
Terminal velocity is based on the atmosphere you're falling through. There IS no terminal velocity in a vacuum.

What he meant is reaching a high velocity that is higher than the terminal velocity in the atmosphere you enter. Which causes deceleration. Which causes heat damage.

Snake-Aes
2010-07-27, 09:57 AM
What he meant is reaching a high velocity that is higher than the terminal velocity in the atmosphere you enter. Which causes deceleration. Which causes heat damage.

Friction doesn't require terminal velocity to burn. It's just the convention they used. Entering an atmosphere suddenly would be more akin to taking falling damage to go from whatever you are to terminal, and then apply the speed burns.

Another_Poet
2010-07-27, 10:01 AM
My suggestion if you don't like the "doubles every round" rules is this:

Re-entering an earthlike atmosphere takes 10 rounds. On each round, you (or your ship) take 10d6 damage, half of which is fire damage and the other half falling damage.

ap

DracoDei
2010-07-27, 04:12 PM
Let me emphasize what others have said that that is re-entry with a large velocity relative to the atmosphere... RL stuff has to do that because carrying enough fuel to decelerate enough to avoid it is not practical. When energy doesn't require reaction mass (as with a Fly spell presumably) then avoiding damage is merely a matter of starting to decelerate far enough out... and since you often have no reason to get up to orbital velocities in the first place...