A269
Quote Originally Posted by Arkhios View Post
"0 hit points and is dying" means you're not at "0 hit points and stable", and you must make death saving throws every turn as normal. Suffocation is very dangerous exactly for the reason that you can't stabilize until you can breathe again. Basically, suffocation can kill you as fast as in two rounds (1 x natural one + 1 failed save), despite your hit point maximum.
It makes sense that if a suffocating creature fails death saving throws, it dies. But what happens if the creature succeeds on the death saving throws (while still not being able to breathe)? According to the death saving throws rules, the creature would become stable. But according to the suffocating rules, the creature can't be stabilized until it can breathe. So there's a contradiction.
If you resolve the contradiction by specific (suffocation) beats general (death saving throws) then there's no point in making death saving throws because successful saving throws are useless.
I think the problem is that the only two mechanics for "dying" are death saving throws and massive damage and neither works in the case of suffocation.