From WoWWiki

The Fel Horde
Main Leader	Kargath Bladefist
Capital	Hellfire Citadel
Main Language	Orcish
Secondary Languages	Possibly Demonic
Member Races	Fel Orcs
Theater of Operations	Outland

The Fel Horde is a new term used by the Alliance & Horde in Hellfire Peninsula, particularly in Hellfire Citadel to describe the fel orcs living there (the fel orcs call themselves the "true horde"). It is believed that this is simply a new term for the Orcs of the Horde's clans affected by the demonic corruption that is being siphoned out of the Pit Lord Magtheridon. Magtheridon is now held captive by Illidan Stormrage, the new Lord of Outland - who uses the Pit Lord to corrupt more orcs to boost his growing army.

The prime constituents (and only example available thus far) of the Fel Horde are Fel Orcs and the demons that operate with them.

Leadership

• Kargath Bladefist - Warchief of the Fel Horde
• Magtheridon - Pit Lord, enslaved by Illidan in order to create more Fel Orcs

Clans of the Fel Horde

The membership of the Fel Horde is largely the remnants of the old Horde of Draenor, which was ruled by the shaman Ner'zhul during the time of the battles Beyond the Dark Portal. It should be noted that many (perhaps all) of the clans listed below are in fact divided, and do not universally support the Fel Horde. (For example, members of the Shattered Hand Clan also reside in Orgrimmar as its rogue's guild and dutifully serve Thrall.) The Shattered Hand orcs that live in Orgrimmar, however, left Draenor twenty years ago and are not fel orcs (they still have green skins and the such).

For our purposes, however, large groups of orcs from the following clans have traveled to Hellfire Citadel and become fel orcs, and now collectively obey Warchief Kargath Bladefist. While the former leaders of these old Horde clans did not all survive, some clans such as the Bonechewer Clan and the Bleeding Hollow Clan still operate under the dominance of their own clan-specific Chieftain as well as Kargath.

• Shattered Hand Clan (Kargath's own clan, possibly rules over the other clans)
• Laughing Skull Clan
• Shadowmoon Clan
• Bonechewer Clan
• Bleeding Hollow Clan
• Dragonmaw Clan

Known members:

Name	Location
Kargath Bladefist	Shattered Halls	Hellfire Citadel
Captain Skyshatter	Dragonmaw Base Camp	Shadowmoon Valley
Chief Overseer Mudlump	Dragonmaw Base Camp	Shadowmoon Valley
Corlok the Vet	Dragonmaw Base Camp	Shadowmoon Valley
Drake Dealer Hurlunk	Dragonmaw Base Camp	Shadowmoon Valley
Grillok "Darkeye"	Zeth'Gor	Hellfire Peninsula
Gug	Dragonmaw Base Camp	Shadowmoon Valley
Horus	Dragonmaw Base Camp	Shadowmoon Valley
Ja'y Nosliw	Dragonmaw Base Camp	Shadowmoon Valley
Keli'dan the Breaker	Blood Furnace	Hellfire Citadel
Murg "Oldie" Muckjaw	Dragonmaw Base Camp	Shadowmoon Valley
Overlord Mor'ghor	Dragonmaw Base Camp	Shadowmoon Valley
Ronag the Slave Driver	Dragonmaw Base Camp	Shadowmoon Valley
Rumpus	Dragonmaw Base Camp	Shadowmoon Valley
Tagar Spinebreaker	Path of Glory	Hellfire Peninsula
Taskmaster Varkule Dragonbreath	Dragonmaw Base Camp	Shadowmoon Valley
Warlord Morhk	Zeth'Gor	Hellfire Peninsula