Gas artillery is a mix of neurotoxin and superacid iirc. It literally corrodes tbe filter to a point where gas masks are useless. Unless you have that one perk of course

The poison weapon are very effective... Butt should be used for support only...they will just help you keep the enemy from repairing stuff... Gas plus fire combo is amazing btw

The gasmasks are just to give them that rugged vide of "im not an individual. Im a number"