The descent, zone by zone
Hellruler has no bottom. The descent runs in five bands; every 100th depth is a boss gate.
Band A · The Land of the Dead
From the graves at the surface down to the Gates of Hell. 10 zones of 100 depths each, 1 gate to a zone. Each zone carries 9 enemies and 1 boss. The Fall of the Damned: 10 enemies and 1 boss.
Band B · The Ante-Hell
Beyond the Gates, before the river: the Vestibule and the yards of hell's intake, down to the Acheron. 9 zones of 500 depths each, 5 gates to a zone. Each zone carries 12 enemies and 2 bosses that take turns at its gates. The Vestibule: 18 enemies and 3 bosses.
The Vestibuledepths 1,001–1,500 · 18 enemies · 3 bossesThe Muster Yarddepths 1,501–2,000 · 12 enemies · 2 bossesThe Branding Pitsdepths 2,001–2,500 · 12 enemies · 2 bossesThe Salt Quarrydepths 2,501–3,000 · 12 enemies · 2 bossesThe Gallery of Masksdepths 3,001–3,500 · 12 enemies · 2 bossesThe Nitre Cellarsdepths 3,501–4,000 · 12 enemies · 2 bossesThe Mirror Hallsdepths 4,001–4,500 · 12 enemies · 2 bossesThe Yoke Fieldsdepths 4,501–5,000 · 12 enemies · 2 bossesThe Acheron Stranddepths 5,001–5,500 · 12 enemies · 2 bosses Band C · The Nine Circles
Past the Acheron: Limbo and the circles below it. 9 zones of 2,000 depths each, 20 gates to a zone. Each zone carries 18 enemies and 3 bosses that take turns at its gates.
Limbodepths 5,501–7,500 · 18 enemies · 3 bossesThe Howling Plainsdepths 7,501–9,500 · 18 enemies · 3 bossesThe Carrion Miredepths 9,501–11,500 · 18 enemies · 3 bossesThe Gilded Crushdepths 11,501–13,500 · 18 enemies · 3 bossesThe Styx Marshesdepths 13,501–15,500 · 18 enemies · 3 bossesDis, the Burning Citydepths 15,501–17,500 · 18 enemies · 3 bossesThe Phlegethondepths 17,501–19,500 · 18 enemies · 3 bossesMalebolgedepths 19,501–21,500 · 18 enemies · 3 bossesCocytusdepths 21,501–23,500 · 18 enemies · 3 bosses Band D · The Foundations
Beneath the floor of hell. 9 zones of 8,500 depths each, 85 gates to a zone. Each zone carries 27 enemies and 6 bosses that take turns at its gates.
The Frozen Deepdepths 23,501–32,000 · 27 enemies · 6 bossesThe Well of Giantsdepths 32,001–40,500 · 27 enemies · 6 bossesThe First Prisondepths 40,501–49,000 · 27 enemies · 6 bossesThe Soulseadepths 49,001–57,500 · 27 enemies · 6 bossesThe Furnace Rootsdepths 57,501–66,000 · 27 enemies · 6 bossesThe Starless Deepdepths 66,001–74,500 · 27 enemies · 6 bossesThe Unmadedepths 74,501–83,000 · 27 enemies · 6 bossesThe Black Sundepths 83,001–91,500 · 27 enemies · 6 bossesThe Last Stairdepths 91,501–100,000 · 27 enemies · 6 bosses Band E · The Heart of Hell
Past depth 100,000 the descent has no end. It carries 36 enemies and 9 bosses that take turns at its gates.