Famitsu has new screens of some of Away: Shuffle Dungeon's bosses, including the first, the "blue crablike thing" Dave encountered at E3: Shuffle Show Floor. It stabs with its pointy legs, and is only vulnerable in the (conveniently) bright red jewel on its chest. The other bosses shown include a big blue worm who lives underwater (not a blue dragon), and a big ambulatory palm tree monster.
These bosses can be fought alone or in the special "Raid Battle Mode" that uses local wireless. In this mode, two players can take on a harder version of a boss, and earn better loot for doing so.