The Grimrail Depot is a transportation hub for the Iron Horde, moving troops and resources from the Blackrock Foundry to the front lines. The Grimrail, a massive train that is the namesake of the Depot, has been outfitted with a weapon capable of shattering the shield that protects the draenei city of Shattrath. Players must fight onto the Grimrail and find a way to bring the Iron Horde’s plans to a halt.