The upper caverns of the Under-Empire are home to hundreds of different species of bats. But these are not all of the bats that dwell in the lightless world of these endless tunnels. One breed lives deep, far below even Hell Pit, and they feast on Warpstone, hence their name: Warp Bats. Skaven miners are always watchful for these creatures, as their presence is a good indication that a lode of Warpstone is nearby.[1a]