showerbomb
The most evil, yet most entertaining thing to do to someone taking a shower; Simply walk in, rip ass and walk out. The humidity will amplify the stench, to the point that even a potential squeaky-no-scent will evolve into a weapon of biological warfare. Bonus points if you are able to trap them in the room with the exhaust fan turned off.
Broseph Primus: Hey, Secundus, who is taking a shower right now?
Broseph Secundus: I think it's Tetria.
Broseph Primus: Perfect. Loose the belt, it's time to make his nostril hairs explode. Let's showerbomb him and blame it on Dad!