My 1st suggestion is that you could spawn a diving suit to breathe underwater and that there would be 2 entities for them, the first one is with a limited amout of air, and the 2nd one is of course an unlimited one. And my 2nd suggestion is... a menu in options for server admins that you could change how many air you can breathe in. And for roleplayers.. the mask screen effect. and that's all, for the owner let's make le best suggestions here to make the best addon ever for le ascending people with lungs1!11!!1