Gehennom (dNetHack)

In dNetHack, notdNetHack and notnotdNetHack, Gehennom is retooled into a somewhat-shorter but more distinct branch compared to its appearance in NetHack. The depths of Gehennom boast more varied demon lords and princes and more elaborate lairs, and the demon rulers themselves are far fiercer than in most variants, to the point that some are better avoided than engaged. Monsters that are killed in Gehennom do not leave corpses if they normally would.

Generation

As in NetHack 3.4.3, Gehennom is situated beneath the Castle, with the Valley of the Dead as its first floor. In all games, the Gehennom branch is a sequence of 20 levels instead of the 20–24 total seen in 3.4.3, with some being randomly chosen and some being the same in every game.

Upper Gehennom

The Valley of the Dead is the 1st level of Gehennom and may generate at a dungeon depth of 25-30. While it maintains the same layout as 3.4.3 Gehennom, it is distinct from it in three main ways:

• There are 7 wages of sin of different sins scattered around the level
• A candle of invocation may be generated on the altar to Moloch if the guaranteed ring of wishes in the Castle was generated with less than 3 stars
• There is a set of three artifact doors past the temple guarding the entrance to Gehennom proper, which can only be unlocked by an alignment key

The 2nd through 6th levels of Gehennom will be randomly generated circular mazes named The Endless Staircase. All levels in The Endless Staircase are generated with a set of monsters:

• A Minotaur
• 3 random major demons
• 6 random monsters represented by the symbol i

There will also be 9 randomly generated items scattered around the level, and as with all items generated in Gehennom, they are more likely to be weapons, armor, tools, and gems. These are also the only levels where the mysterious force will be active during the ascension run, being completely absent on all other levels in Gehennom. All levels of The Endless Staircase have diggable floors and walls and are eligible to generate hell vaults.

Immediately following The Endless Staircase, the 7th through 9th levels will be The Wizard's Tower. The Wizard's Tower itself retains the same layout as seen in 3.4.3, and the same types of random monsters are generated, though there is a higher likelihood of high-level ancients being generated within:

• The top level of the Wizard's Tower has 4 randomly chosen major demons
• The bottom level of the Wizard's Tower has 3 randomly chosen major demons

The Wizard of Yendor may now also generate with some unique artifacts placed at his feet:

• A spellbook of secrets (10%) that hasn't been generated yet, or a generic artifact spellbook of secrets otherwise
• The blessed +7 Staff of Wild Magic (5%)
• The blessed +7 Robe of the Archmagi (5%)
• The blessed +7 Hat of the Archmagi (5%)

The Infinite Layers of the Abyss and the Nine Hells

In every game, three layers of the Abyss are included in Gehennom, as well as all three fake wizard tower levels. After the Wizard's Tower, the 10th and 11th levels will be randomly chosen from:

• The first layer of the Abyss:
  • The 222nd — Slime Pits, Juiblex's realm
  • The 222nd — Shedaklah, Zuggtmoy's realm
  • The 422nd — Dun Savannah, Yeenoghu's realm
  • The 600th — Lyktion, Baphomet's realm
  • The 600th — Bone Plateau, Pale Night's realm
  • The 23rd — Iron Wastes, Kostchtchie's realm

• The second layer of the Abyss:
  • The 113th — Thanatos, Orcus's realm
  • The 570th — Shendilavri, Malcanthet's realm
  • The 45th, 46th, and 47th — Azzagrat, Graz'zt's realm
  • The 66th — Demonweb, Lolth's realm

• The third layer of the Abyss:
  • The 88th — Brine Flats, Demogorgon's realm
  • The desiccated 88th — Salt Flats, realm of Lamashtu, the demon queen of the future
  • The 89th — Shadowsea, Dagon's realm

• Or one of the three fake wizard tower levels. The two-way magic portal that leads into the Wizard's Tower is accessible from the structures in one of these levels, which are on standard maze levels that may also generate hell vaults.

The 12th level is the third "hell" level and will be randomly chosen from:

• The realm of Bel, Lord of the First — Avernus
• The realm of the Chromatic Dragon on the First — Dragon Caves
• The realm of Dispater, Lord of the Second — Dis
• The realm of Mammon, Lord of the Third — Minauros
• The realm of Belial, Lord of the Fourth — Phlegethos

The 13th and 14th levels of Gehennom will again be randomly chosen from either a layer of the Abyss or a fake wizard's tower The 15th level of Gehennom is the second "hell" level and will be randomly chosen from:

• The realm of the creature in the ice, Lords of the Fifth — Stygia.
• The realm of Lilith, Lord of the Sixth — Malbolge
• The realm of Baalzebub, Lord of the Seventh — Maladomini
• The realm of Mephistopheles, Lord of the Eighth — Cania

The 16th and 17th levels of Gehennom will again be randomly chosen from either a layer of the Abyss or a fake wizard's tower

Lower Gehennom

The last 3 levels of Gehennom will always be Nessus, the level containing the vibrating square, and Moloch's Sanctum.

Nessus is the 18th level of Gehennom and the last of the three hells, immediately above the Vibrating Square level.

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----------------------------------------------------------------------------

Four of the five marked downstairs are non-functional decoys (chosen at random). Trying to go down the four fake downstairs stairs will give the message "These stairs don't go down!" and take you nowhere. It is the 9th hell in many versions of the D&D cosmology.

The level containing the vibrating square is always the 19th level of Gehennom, immediately below Nessus. The vibrating square trap cannot be found through magical means but will display messages in a 3-square radius indicating it is near. After performing the invocation with either the bell, book, and candelabrum or with a suitable bell substitute for the relevant roles (Otiax for Binders, The Annulus for Anachrononauts or The Silver Key for any role), the stairs leading down to Moloch's Sanctum will be revealed.

The layout of Moloch's Sanctum remains unchanged, though there are a few additional monsters placed throughout the level:

• A shambling horror placed randomly on the level
• A stumbling horror placed randomly on the level
• A wandering horror placed randomly on the level

The Amulet of Yendor is also now guarded by the elder priest instead of an aligned priest of Moloch.

Alongside the normal considerations for taking on the Sanctum, it is important to not be troubled by madnesses while at low sanity, especially when fighting the elder priest, who is also formidable in their own right and cannot be warded against. They possess a paralyzing gaze attack and a "deadly tentacles" attack that can either shred a character's worn armor or remove them; characters who have their armor removed are at great risk of suffering very bad effects that may kill them outright.