D&D 5E Low/High Gravity mechanics

TheNoremac42 · Nov 25, 2017

I'm currently in the process of creating a sci-fi homebrew, and something I want to include are times when artificial gravity might change drastically (such as during technical issues on the spacecraft) or when the characters go to a planet with a noticeably stronger or weaker gravitational pull than what they are used to.

Does anyone have any suggestions or materials I could look up that could help me determine mechanics for different levels of gravity?

Morrus · Nov 25, 2017

In WOIN (which isn't D&D) I had gravity you're unused to creating fatigue after an hour, and both high and low counting as difficult terrain unless you are trained in it. Zero-g has some additional effects. Also high and low grav double/halve falling damage and jump distances.

TheNoremac42 · Nov 25, 2017

Morrus said:
In WOIN (which isn't D&D) I had gravity you're unused to creating fatigue after an hour, and both high and low counting as difficult terrain unless you are trained in it. Zero-g has some additional effects. Also high and low grav double/halve falling damage and jump distances.

So for Low Gravity (let's say 0.5g - 0.75g), a character has doubled jump height, advantage on STR checks, disadvantage on DEX checks, suffers from difficult terrain (unless trained or properly equipped), and one level of exhaustion after an hour (unless trained or properly equipped). The effect is multiplied at even lower gravity.

For High Gravity (1.5g - 2g), a character has halved jump height, disadvantage on STR and DEX checks, fall damage is doubled, suffers from difficult terrain (unless trained or properly equipped), and has one level of exhaustion after an hour (unless trained or properly equipped). The effect is multiplied at even higher gravity.

Nevvur · Nov 25, 2017

I think that's a good implementation. There may be some temptation to create a more diverse set of advantages and disadvantages based on finer increments of gravity variance, but IMO this runs counter to the design philosophy of 5e.

TheNoremac42 · Nov 25, 2017

What about zero gravity? Definitely be considered difficult terrain, but what else?

Morrus · Nov 25, 2017

TheNoremac42 said:
What about zero gravity? Definitely be considered difficult terrain, but what else?

Guess it depends how scientifically accurate you want to be. A super easy method is you get a a fly speed equal to half your normal speed, and any damage you take pushes you 5’ for every 5 points. But you could go down a whole rabbit hole of physics!

Lanefan · Nov 25, 2017

Morrus said:
Guess it depends how scientifically accurate you want to be. A super easy method is you get a a fly speed equal to half your normal speed, and any damage you take pushes you 5’ for every 5 points. But you could go down a whole rabbit hole of physics!

In any sort of enclosed area it's not so bad; if you start drifting somewhere you'll eventually just hit a wall/floor/ceiling/etc. and be able to push back off.

In a non-enclosed area? Messy...

Lanefan

Morrus · Nov 25, 2017

Lanefan said:
In any sort of enclosed area it's not so bad; if you start drifting somewhere you'll eventually just hit a wall/floor/ceiling/etc. and be able to push back off.

In a non-enclosed area? Messy...

Lanefan

Well, depends on air resistance. Zero-g doesn’t mean a vacuum, or vice versa.