It adds a new campaign level and challenge map 'Fistful of Coins', which has waves of enemies storm you in exchange for loot. These maps "perfect for co-op."
"When we finished the game back in May we had a few months to wait before the Summer of Arcade was over. So we devoted ourselves to building the kind of maps that we wanted to play: fiendishly difficult ones that are perfect for co-op," said Max Hoberman.
Crimson Alliance released for Xbox 360 via XBLA. What the heck did we think of this co-op dungeon crawler? Check out our review to find out. Spoiler: we liked it.