I was just experimenting with Construction Foam, and I realised that a CF Sprayer could be used as a "gun" when combined with Sand to instantly suffocate opponents, since it can be launched in the same hitbox as a player/mob.
I did further experimentation, and I concluded that since Armor doesn't protect against CF, it could be used to kill Gem Armor (dun dun dun dun).
I even guess that CF and Water can cause immediate drowning.
Thoughts?