Blood and souls for Makhleb!
Henzell says...
  1. An infinite dungeon branch, Pandemonium consists of an infinite number of dungeon-type levels. Pan levels are populated with demons instead of dungeon monsters. An entrance is guaranteed on Depths:2.
  2. Almost all Pan levels contain a vault, containing a demon lord (&), maybe some loot, and maybe a rune. There are four unique demon lords each with a unique rune (Mnoleg, Lom Lobon, Cerebov and Gloorx Vloq); other demon lords are randomly generated and may guard a demonic rune.
  3. There are a few random Pan lord vaults (draining_boxes, hellion_island, hall_of_smite, pan_frozen_over) with a guaranteed demonic rune. Other random Pan vaults have a chance of containing either a rune (1/9) or an exit (2/9).
  4. <evilmike> minqmay: pan is like when you go on a long road trip, you always forget something

Information based on master branch and the great LearnDB.
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