With the WoW Anniversary World Boss Doomwalker now dropping the new Azure Worldchiller mount, the previous mount Illidari Doomhawk, added in 2021, is now available for sale in vendors.
During the WoW Anniversary, Historian Ma'di sells many previous anniversary event items and is located at Caverns of Time.
Her inventory now includes Illidari Doomhawk, which costs 0 Timewarped Badge and should be able to be purchased every year without any fear of missing out on this mount.