This is going to be story where metal bands go to Hogwarts.
Okay, so here are the houses with the bands that are in them.
Gryffindors: Turisas, Children of Bodom, Dethklok, Sabaton
Ravenclaws: Wintersun, Ensiferum, Eluveitie
Hufflepuffs: Korpiklaani, Alestorm
Slytherins: Slipknot, Immortal, Behemoth