It's a bunch of severed heads mounted along the walls, all saying different things ranging from encouragement to things worthy of an AO rating.
For shits and giggles, the boss would be 5 enemies that are weak, but constantly revive each other and all do different things and share a very large health pool. Think the Madarame fight but without a main body to attack. Halfway through, they use a unique skill to lower the player's entire party down to 1 HP, but then they start arguing and attacking one another.
