Huehuehue. Those are usually among the safest of the four Arcana mod mapgen additions. The more hazardous monsters are a floor down and further blocked by a sealed-up door, while the real Fun is yet another floor down, with even more stuff in the way.
In contrast, the other three sites are littered with the more hazardous monsters from the starting area on up.
Of course, if you have z-levels enabled all of these might be more hectic. I had to do a lot of messing around with the floating temple to prevent the Archon from flying THROUGH the roof and back down, via getting getting aggroed by monsters on ground level.
