Go down in the dungeon. Kill everything you meet. Backstab your friends and steal their stuff. Grab the treasure and run.
Admit it. You love it.
Now, since this is a tournement, you may end up playing Munchkin Supers, Munchkin Fu, Star Munchkin, Munchkin Bites, or some combonation there of. Winners from the preliminary rounds will go on to the semi-finals.