（Nathreza） is the home world of the Nathrezim, more commonly known as dreadlords, one of the first species to join the Burning Legion. Nathreza was a collection of rocks imbued with potent magic, floating amid the infinite void of the Twisting Nether. A tiny sun orbited it every few minutes, and dozens of miniature glowing moons followed it. Bits of rock floated in the air, held aloft by magic. There was a city of basalt towers lit by the flare of green fel lanterns, and basalt discs rose up the sides of buildings. In the center of it all was one gigantic windowless tower amid a grid of green energy flows, with green runes lighting up its sides. The dreadlords rarely use their written language outside of their homeworld.
Just before the war in Outland, Illidan Stormrage opened a portal to Nathreza fueled by the souls of his own soldiers and draenei loyal to Maiev Shadowsong. Illidan and his demon hunters slaughtered Nathreza's defenses and discovered the location of Argus within the dreadlords' records. When they returned to Outland, the magical force of the portal closing destroyed Nathreza and dealt the single greatest defeat the Legion had suffered in millennia. The demons who died on Nathreza died for good.
Their homeworld is likely the world where the Dreadlords established their citadel seen in The Dreadlords Convene, an interlude from the Undead campaign in Reign of Chaos. If so, their world is in the Twisting Nether like Outland is. However, given the number of worlds consumed by the Legion, the Citadel could reside on another Nathrezim world, or even on Argus.
Mal'Ganis said he was going to travel to the homeworld after being discovered as Barean Westwind, but as it had already been destroyed by Illidan at that time it is unclear what happened to him.