Colossal Wraithbound Mawrat

Head to Zereth Mortis and make your way to the pyramid area at 60, 32, where two Mawsworn Supply Chests spawn on the front left and front right of the pyramid base, and a third spawns below the stairs to the left beside the cages.

Loot the chests at 60, 32 — the chest on the left base side of the pyramid can be looted from on top of the pyramid without aggroing the nearby mob. Three additional confirmed chest spawns are clustered at 60.18, 31.07, with individual spawn points at 59.4, 31.39 and 60.10, 32.35, and a further spawn at 60.95, 30.55.

An alternative farming location is Antecedent Isle in the northern part of Zereth Mortis, with a chest spawn confirmed at 48.73, 46.12, where a new chest appears roughly every 15–20 minutes per realm.

Realm hop using Antros groups to access fresh chest spawns across multiple realms — the mount can drop from any Mawsworn Supply Chest regardless of how many you have already looted that day, so chests beyond the first are still valid loot sources.

Classes with stealth have a significant advantage at the pyramid cluster around 60.95, 30.55 and the surrounding area, as the zone is heavily populated with mobs and Wardens that can be aggroed while looting chests.