Peruvian Hand Grenade
The act of farting into an empty gatorade bottle (or container with similar liquid volume capacity), capping it, and tossing it to a friend (or foe), for him (or her) to later open and be greeted with the gift that keeps on giving...flatulence.
"Oh my god, bro. Why did you tell me to open that, it was foul!"
"Don't be scared, girl, it's just the ol' Peruvian Hand Grenade."
"Don't be scared, girl, it's just the ol' Peruvian Hand Grenade."