Shadowmoon clan (alternate universe)

The Shadowmoon clan, led by their chieftain, were orcs that made their home within. The Shadowmoon had a history of astrology, they had always spoken the language of the stars, the earth, and the moon, but now heard another - the voice of shadow. A key source of the Shadowmoon clan's power came from their understanding of the stars and their omens. For centuries, they recorded the patterns of the stars and their interpretations. They were profoundly linked to the spiritual world and had many seers, astrologers, and speakers of the dead among their ranks.

History
The Shadowmoon clan have always derived their magic from the stars, earth, and moon. Communing with the ancestors is extremely important and often done through Ancestral Talismans of the ancestors, as well as ceremonial tattoos for clearer communication with the ancestral and elemental spirits.

Several centuries ago, when the Genedar arrived on Draenor, the Shadowmoon clan witnessed the crash in the sky. A piece of the ship crashed down in Shadowmoon Valley, and soon afterward a shadow appeared in the sky that came to be known as the Dark Star by the orcs; in reality, the Dark Star was the naaru K'ara in a Void state, ejected from the Genedar during the crash.

By observing the Dark Star, the Shadowmoon clan discovered the powers of the Void. But when orcs began to use the shadow powers to defile the spirits of their sacred ancestors, the chieftain outlawed the shadows and the magic of the Dark Star.

Warlords of Draenor
Three centuries later, before the war in Draenor, the Shadowmoons were still largely peaceful, but eventually became reclusive as the conflict approached, withdrawing into their fortifications. When the Iron Horde began its march across Draenor, the clan's chieftain Ner'zhul was given an ultimatum by Grom Hellscream: join or die. The Shadowmoon were not a war-like clan by tradition, but Ner'zhul joined with the Iron Horde in order to save the lives of his clansmen. Hellscream also ordered Ner'zhul to provide a worthy form of power or else he would kill the Shadowmoon anyway, as he lacked interest in their astrological and prophetic traditions. Ner'zhul, with the fate of his clan on the line, broke the ancient laws and called on the power of the Dark Star, gaining mastery over the Void. Using the Void, the Shadowmoon clan raises undead and calls in creatures of shadow to battle their foes. Their nobility has been sacrificed for necromantic power, making them little different from the Scourge that a different version of Ner'zhul once commanded.

A faction of discontent orcs, led by Ner'zhul's mate Rulkan, still stands by the old laws that ban Void magic and have formed the Shadowmoon Exiles to combat Ner'zhul's followers.

Darion Mograine sends the adventurer into Shadowmoon Burial Grounds to investigate Ner'zhul's early studies on how to bind souls and control the undead, referring to the void-using Shadowmoon orcs as warlocks. The imp Impsy also sends the adventurer into Shadowmoon Burial Ground because things happening on Draenor are causing ripples in the Twisting Nether and requires a Void-Gate Key twice to prevent the worlds from collapsing into the void (both times). It seems at some point, Alleria Windrunner had fought against these Shadowmoon clan orcs. Eventually, Alliance and Horde shaman prepared a ritual to return the disturbed souls back to rest. They arrived to the Burial Grounds to perform it.

Battle for Azeroth
In time, the Shadowmoon clan joined with the other Mag'har orc clans under the command of Warchief Grommash Hellscream. As the Mag'har and Lightbound clashed, events on Azeroth would see to a new war between the Horde and the Alliance. In the midst of this, Eitrigg sought to travel to the alternate Draenor and call upon the debt the Mag'har owed to the Horde for liberating them from Garrosh Hellscream's meddling and the Burning Legion's corruption.

As the entire Lightbound army was marching towards the Mag'har, Grommash ordered for the Mag'har to follow Geya'rah and fallback to Azeroth. Thus, when Warchief Hellscream and Lantresor of the Blade charged at the Lightbound, Eitrigg activated the shard of the Vision of Time in his possession in order to return to Azeroth with his new allies. After their arrival on Azeroth, Overlord Geya'rah took her place as leader of the Mag'har and pledged the loyalty of her people to Warchief Sylvanas Windrunner and the Horde.