The first barracks room has another passage leading to a room of treasure. There are also two plaques one on each side of the pillars that are on each side of the central walkway , which read:

We gladly welcome all visitors. He mentions that the world has been invaded by Kreegan and that you will need very special weapons and armor to kill their elite guards. Special Offer.

A large fireball shoots down this corrdior at regular intervals. This opens up into another very large chamber with lots and lots of eyes. He has these weapons, but will only hand them over to you with a Control Cube.