The Infernal Isles:
Avernus – ruled by Lord Graz'zt – Mostly destroyed the volcano of Pandemonium. Capitol: The Bronze Citadel.
Dis – ruled by Emperor Orcus (ruling on behalf of The Sultan of the Efreet) – Capitol: City of Brass.
Minauros – ruled by Lady Hecate – The wealthy city of Jangling Hiter, the city of chains, floats above this toxic swamp of an island. Capitol: Jangling Hiter.
Phlegethos – ruled by Lord Jubilex – Island of volcanic swamps, home to slime-like demons. Capitol: Abriymoch.
Stygia – ruled by Lady Levistus – Burning deserts, chilly swamps, factories and prisons. Capitol: Tantin.
Malbolge – ruled by Lord Demogorgon – A rocky slope of black stone, surrounding a dark, inscrutable jungle. Capitol: Abysm (aka Gaping Maw).
Maladomini – ruled by Lord Baalzebul – Mostly in ruins. Nearly devasted by the legion of Orcus in putting down Baalzebul's rebellion during the Interregnum. Capitol: Malagard.
Cania – ruled by Lord Mephistopheles – Frozen within this icy island are lost cities and entire armies. Capitol: Mephistar.
Nessus – ruled by Lady Glasya – A place of soaring chasms and bottomless pits. Capitol: Malsheem.