Make sure you don't inhale any of the fumes you want other people to inhale. A previously submitted mask that has a belt mounted canister to replace the grenades. Resubmitted as part of a pack, optimized and touched up. Not actually/intentionally based on ...

Caution, dangerous chemicals! Contact with skin may cause severe blistering, allergic dermatitis and death. May also be set on fire and spread around by a dangerous lunatic....

Steal a grenade launcher from the Demoman, saw it down to size in front of his weeping eye and use it to shoot all sorts of grenades, chemical canisters, tear gas or the Pyro's favourite, anything flammable. Flare gun, includes own projectile....

T-they are using DOORS to avoid a horrible death? Tear it down with an axe that can break anything! Note: there are things this axe cannot break....