Sinking speed

Olgar Shiverstone · Sep 1, 2008

This came up yesterday while running an extensive, 3-dimensional underwater combat. How fast does a PC sink in water?

There don't seem to be any guidelines in the DMG or Stormwrack except for the underwater movement rules (1/2 speed as a full-round action with a DC 10 swim check) -- but those lead to the absurdity that a character in full plate sinks to the bottom more slowly than an unarmored character!

Trouvere · Sep 1, 2008

Manual of the Planes p. 77 suggests a flat sinking rate of 30'/round (15' in the first round only). Characters carrying less than 5 lb of equipment rise at the same rate. This is probably a lot more sensible than trying to calculate terminal velocity in water for each PC!

Olgar Shiverstone · Sep 1, 2008

That sounds reasonable. Why is it in the Manual of the Planes of all places? You'd think rules for combat and adventuring underwater be where you'd look for other underwater adventures.

Trouvere · Sep 1, 2008

Well, it's in the section on the Elemental Plane of Water, of course. It's not entirely appropriate, since it's one of those planes where you can consciously choose which direction is up. The falling/rising rules are given as alternative modes of movement to just swimming. Since most characters won't have a swim speed as high as 30', 'falling' would be a quicker way to travel. On a material plane, that won't matter.

Jhaelen · Sep 2, 2008

Olgar Shiverstone said:
That sounds reasonable. Why is it in the Manual of the Planes of all places? You'd think rules for combat and adventuring underwater be where you'd look for other underwater adventures.

Yup, I'd never have thought of that. I'd have ruled it was similar to levitating, i.e. 20ft per round.

You learn something new every day!