Deadly Rooms of Death/YMMV


 * Excuse Plot: Definitely King Dugan's Dungeon and most user holds, but averted with Journey to Rooted Hold, The City Beneath and some other user holds, where the plot is actually important and affects what kind of rooms show up.
 * Goddamned Bats: Anything in the hands of a competent architect. Wraithwings typically get the most hatred, though, since they can fly, will run away from the player if alone (typically over pits) but in hordes, will swarm the player in a hard-to-predict fashion (since their movement is dependent upon the location of other wraithwings and the movement order of the whole horde).
 * That One Level: Whichever one you're stuck on. Consensus says that Levels 8 and 13 of KDD definitely fall into this state, and there are also particularly nasty rooms spread throughout the series. In addition, some user-made holds are infamously difficult.
 * The official level set Beethro's Teacher consists entirely of Those Six Levels.