Dungeon Mayhem: Monster Madness

From BoardGameGeek:

In Dungeon Mayhem: Monster Madness, you play as one of six epic D&D monsters, each with their own way to charm, crush, disintegrate, and devour their foes. Store all your Dungeon Mayhem cards in this monster-sized box, then select your favorite character and pit it against any other deck in the game line. Plus, you can enjoy bringing more adventurers into the fold with new rules to allow for mayhem with up to six players at once!