👉 Gehennom is the fiery, unforgiving underworld that makes up the second half of the game. It is a grueling test of endurance, resistance, and navigation.
Location: Begins immediately below the Underground Castle (which is at level 23 to 25). Gehennom spans 18 to 21 levels.
It is the domain of demon lords, powerful undead, and the dreaded Wizard of Yendor.
Characteristics
- Layout: The vast majority of Gehennom consists of winding, repetitive maze levels carved from solid rock. The walls cannot be modified by regular pick-axes (though they can be destroyed by wands of digging).
- Environment: There is no natural light. Fire traps and lava are omnipresent. Fire resistance is practically mandatory for survival.
- Teleportation: Teleportation is heavily restricted in Gehennom. You can teleport to escape danger, but you cannot use level teleportation to quickly ascend or descend, except on a few specific levels.
Special Levels and Branches
Gehennom is home to numerous unique locations and challenges:
- Valley of the Dead: The very first level of Gehennom, packed with graves, undead, and a temple to Moloch.
- Demon Lairs: You will encounter the domains of several demon lords, including Dis, Maladomini, Jubilex's Realm, Orcus Town, Lair of Tarrasque, and Yeenaghu's Domain.
- Vlad's Tower: Branches upwards from the middle of Gehennom.
- Wizard's Tower: A heavily guarded structure where the Wizard of Yendor waits with the Book of the Dead.
- Plane of the Modron & Hellish Pastures: Unique GnollHack branches accessible via portals in Gehennom.
- The Vibrating Square: A hidden, unremarkable-looking square on the lowest regular level of Gehennom. You must find it to perform the Invocation.
- Moloch's Sanctum: The final level of Gehennom, accessed only after performing the Invocation on the vibrating square.