Grumblejack McDoogan is a vendor in Corepunk. It has 1 known spawn location on the Kwalat map. It sells 876 items.
This strange old man is stuck on the toilet, and claims that if he moves his arse will explode and he will die. He desperately needs you to bring him something to defuse the bomb stuck in his arse. He's very weird, swears, and might just be crazy - it's very hard to tell. He also claims to be selling brownies, which is a concerning prospect from a bloke sitting in a toilet. He's darkly comedic, random, and surprising.