Okay, here's how it works... I will say two bands and the next poster has to pick their favourite out of the two. Then, they carry their favourite over into their post and put them up against another band. For example:

Metallica vs. AC/DC

Then if someone picked Metallica, they would say Metallica vs. [insert band here] and the game carries on like this

So my first one is Metallica vs. AC/DC