Gas Mask

[NowBobCat]

Do I get the gas mask in the area with the gas, or do I find it in another part of the game?

[Groen90]

technically it's there, but the only way to access it is through another area connected to it; won't go into details in case you don't want spoilers, but if you need directions there's a very helpful guide by Demajen in the guides section

[Cookie]

You will need it for the Abbys, but for fungal erea you should be fine without it, thing is you get it late and it kinda hidden, level design smh. Good luck.
It's in a Respite B2 room, but you get there through upper erea.