Here's a few lords and princes:
Name CR Source
Demon Lord, Turaglas 30 Dragon#312
Demon Lord, Aldinach 20 Necropolis
Demon Lord, Baphomet 25 Tome of Horrors 1, Lost Caverns of Tsojcanth, 1E Monster Manual 2
Demon Lord, Gatekeeper 27 Ultimate Monsters 1
Demon Lord, Gholl 21 Necropolis
Demon Lord, Iyaviht 27 Ultimate Monsters 1
Demon Lord, Jubilex 28 Tome of Horrors 1, Book of Vile Darkness, 1E Monster Manual 1
Demon Lord, Kostchtchie 26 Tome of Horrors 1, Lost Caverns of Tsojcanth, 1E Monster Manual 2
Demon Prince, Abaddon - Armies of the Abyss
Demon Prince, Abraxas - Armies of the Abyss
Demon Prince, Anarazel - Armies of the Abyss
Demon Prince, Astaroth - Armies of the Abyss
Demon Prince, Azazel - Armies of the Abyss
Demon Prince, Azidahaka - Armies of the Abyss
Demon Prince, Behemoth - Armies of the Abyss
Demon Prince, Dagon 30 Tome of Horrors 1
Demon Prince, Decarabia - Armies of the Abyss
Demon Prince, Demogorgon 30 Book of Vile Darkness, 1E Monster Manual 1, Immortals Boxed Set
Demon Prince, Eligor - Armies of the Abyss
Demon Prince, Flauros - Armies of the Abyss
Demon Prince, Fraz-Urb'Luu 30 Tome of Horrors 1, Dragon#333, Lost Caverns of Tsojcanth, 1E Monster Manual 2
Demon Prince, Gamigin - Armies of the Abyss
Demon Prince, Graz'zt 24 Book of Vile Darkness, 1E Monster Manual 2, Lost Caverns of Tsojcanth
Demon Prince, Haagenti - Armies of the Abyss
Demon Prince, Ipos - Armies of the Abyss
Demon Prince, Marbas - Armies of the Abyss
Demon Prince, Nocticula - Armies of the Abyss
Demon Prince, Orcus 28 Tome of Horrors 1, Book of Vile Darkness, Dungeon#89, Eldritch Wizardry, 1E Monster Manual 1, Rappan Athuk 3, Immortals Boxed Set
Demon Prince, Pazuzu 29 Dragon#329, Tome of Horrors 1, 1E Monster Manual 2
Demon Prince, Raum - Armies of the Abyss
Demon Prince, Sabnach - Armies of the Abyss
Demon Prince, Seere - Armies of the Abyss
Demon Prince, Shax - Armies of the Abyss
Demon Prince, Socothbenoth - Armies of the Abyss
Demon Prince, Vepar 21 Tome of Horrors 2, Armies of the Abyss
Demon Prince, Yeenoghu 22 Book of Vile Darkness, 1E Monster Manual 1
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