Just a little idea that popped into my head the other day. If you, for example, run into a group of enemy oozes, you could pop an ooze tonic to make sure they don’t attack you. Would be a very useful PvE feature, and actually give tonics a function other than walking around until you zone/logout.
This would also be hilarious in WvW (if your name didn’t appear over your head while using tonics) as you could jump in a group of mobs, turn into one of them, and have your chasers figure out whether you turned into one of them, or if you stealthed out of there. I can only imagine how funny it must be to watch them from a distance while they’re slaughtering every mob, hoping you’re one of them.