man grenade bath blaster

When a man lets out a gigantic, colossal fart in the bath tub.

Greg: Did you hear Frank's man grenade bath blaster after he ate all that Chipotle last night? It shook the house, I swear!
Bill: You mean I stayed in the bunker all night, thinking it was an earthquake, for nothin?
Greg: Well, at least you were partially spared from Frank's wrath.