This is an updated version of the Gas Mask idea.
This is an idea of how the gas mask could be ingame when in first person. My suggestion is that the devs implement some areas on the map that have some kind of poison/radiation/something in the air that will require the players to use the gas masks not to get sick. This way, the gas masks are more than something just for show. These areas with poisoned air could have some signs showing that gas masks are recommended.
In this video, I illustrate three stages of the mask: pristine, worn with rain effect and ruined.
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