Sheol is a new dungeon branch not found in vanilla NetHack. It was added originally in UnNetHack, and later in Slash'EM Extended and SLASHTHEM, but with important differences. It is accessed by a stairway from the main dungeon in Gehennom and represents a kind of icy underworld (a "frozen-over" hell), in contrast to the fiery hell of Gehennom proper. It contains special ice-themed monsters, traps, and terrain types.
The original description of this branch can be found in Sheol.txt.
Sheol contains a special middle level and bottom level, as well as a number of filler levels. The filler levels feature ice floors and water tiles, as well as new types of walls made of ice. They may also contain randomly placed clouds. Filler levels after the middle level become narrower.
Each filler level has a 33% chance of containing a wand of fire, which in the hands of the player may make clearing a path through the ice easier, but in the hands of a monster creates a new danger for the adventurer.
The Sheol branch now contain the entrance to Vlad's Tower.
Two tombstones can appear in a random location on the final level, "Isaac - Sacrificed by Mother", and "Guppy - Beloved by Flies", with a 10% and 30% chance to appear respectively. This is a reference to the video game The Binding of Isaac. These graves should have a human and cat corpse, respectively, but this is not implemented.
Sheol contains two new types of ice-based walls, ice walls and crystal ice walls. Both are represented by the 8 glyph. The regular ice wall can be removed by fire or digging with any digging tool, but the crystal ice wall is impervious to any form of removal except fire or the rare crystal pick. The regular ice wall takes less time to clear than a regular (stone) wall. Removing either type of ice wall leaves a floor of ice behind.
Sheol contains a new type of trap, the cold trap, which in UnNetHack is generated only within this branch. The cold trap's threat to players is analogous to the fire trap found elsewhere in Gehennom: they deal cold damage, which can destroy potions in the player's inventory.
- blue slime
- white naga
- white naga hatchling
- ice golem
- crystal ice golem
- dark Angel
- Punisher (not randomly generated, but one appears in 50% of randomly generated levels)
- Executioner (unique)
SLASHTHEM and Slash'EM Extended implement the Sheol branch, but with important differences from the UnNetHack version.
Beware of Father Dagon and Mother Hydra at the final Sheol level. They both are capable of +100 damage in one turn, so keep your guard up.
Sheol is a term associated with the afterlife in Judaism. Depending on the context, it may be understood as the place where the wicked go after death (i.e. Hell), or as the destination of all who die, regardless of character (similar to the Greek Hades). English translations of the Tanakh (Hebrew Bible) sometimes translate the expression as "the grave".