The Gluss'sa'Nikto (from Lords of Nal Hutta) have the Swimmer species ability. Much like species with Amphibious, Swimmer removes the penalties for moving through water. However, rather than breathing water (as Amphibious allows), Swimmer doubles the time before a character begins to drown.

It's obvious how this works when submerged, but should this also allow the character to double the time before other types of suffocation set in? If the character is able to hold his breath much longer when swimming, shouldn't he be able to do the same when trying to avoid smoke inhalation or when in vacuum (ignoring real science where holding your breath in vacuum is a really bad idea, this game uses suffocation rules for vacuum as a base bfore adding other unpleasantness)?

I would say smoke/gas yes, vacuum no. I can't suspend that much science in vacuum's case.

The vacuum rules already have you holding your breath. I'm just wondering if this trait should double that time.

GMs discretion. I go with realistic, trying to hold your breath likely results in death. Unconsciousness in like 10 secs. Cardiac arrest is likely in less than 60 secs. If you don't recompress within 90 you're a goner and if you do you're still likely pretty jacked up. I don't suspend reality like that. Up and down still apply, and being in a vacuum is a death sentence.

Try to hold your breath in a vacuum and you will kill yourself a lot quicker. Boiling blood, self-induced nitrogen narcosis and/or the bends, etc….

In a vacuum, you actually want to exhale as much as you can, then hold it. The less air you have in your lungs, the less likely you are to suffer from problems with rapid extreme decompression.

That said, being a swimmer might help you hold your breath in those kinds of circumstances, so long as you know to fully exhale first.

I know that I can sit on the bottom of a pool for a minute or two, but only after I have fully exhaled all the air from my lungs. Then I can sink to the bottom. Otherwise, I’ve got too much air in my lungs and I float.

GMs discretion. I go with realistic, trying to hold your breath likely results in death. Unconsciousness in like 10 secs. Cardiac arrest is likely in less than 60 secs. If you don't recompress within 90 you're a goner and if you do you're still likely pretty jacked up. I don't suspend reality like that. Up and down still apply, and being in a vacuum is a death sentence.

Wait - you're saying that Total Recall LIED to me?!?

(subtitle: Ah-nold on Mars comically suffocating from lack of air, but then being fine the very next scene when Mars gets air)