Railmaster Pauli Rocketspark, chief foreman of the Grimrail Depot, has been enlisted by Garrosh Hellscream to build the technology required for the Iron Horde's infrastructure. Given the dim-witted assistant Borka to do the heavy lifting, Rocketspark set about building the Grimrail.
With a zeal for flame and explosives, Nitrogg was a natural fit in the mechanized and weaponized army that Garrosh's plans brought to Draenor, and he has risen quickly through the Iron Horde. He oversees the artillery on the Grimrail, and is eager to break through the defenses around Shattrath and conquer the enemies of the Iron Horde within.
Before the rise of the Iron Horde, Tovra had never ventured beyond the frigid tundra of Frostfire, where she led groups of Thunderlord trackers to snare and capture the fiercest rylaks on Draenor. Her mastery of rylaks has made Tovra an invaluable asset, and she now commands the aerial forces of the Iron Horde.
Sadana Bloodfury is a powerful acolyte of the Shadowmoon clan, deeply connected to the lunar cycles. When the whispers of the dark star worked their way into the hearts of the Shadowmoon, Sadana followed her chieftain Ner'zhul into their clan's burial grounds, using her powers to lure the spirits of the dead for a twisted purpose.
When Ner'zhul tore the fabric of reality and allowed the Void to spill into the ritual burial grounds of the Shadowmoon clan, the malefic spirit Nhallish came through that rift in search of souls upon which to feed. Ancient and born of pure darkness, Nhallish seeks to devour all life.
Deep within the subterranean caverns under Shadowmoon Valley, the carrion worm Bonemaw has a symbiotic relationship with Ner'zhul's followers: The creature feasts upon the dead left in the wake of the Shadowmoon cult's dark rituals, and in return it serves as a formidable guardian of Ner'zhul's inner sanctum.
Ner'zhul, chieftain and elder shaman of the Shadowmoon clan, sacrificed the heart and soul of his tribe in an attempt to join the Iron Horde. He has now retreated to his clan's ancient burial grounds as he ventures ever further along a dark path, embracing the power of the Void and the necromantic arts.