Felsteel Annihilator drops from Archimonde in Hellfire Citadel on Mythic difficulty. It can also be listed on the Black Market Auction House.
Here you can buy Felsteel Annihilator for EU or US Servers.
You'll get guide for getting Felsteel Annihilator
• You'll be able to get Felsteel Annihilator
• Felsteel Annihilator mount
• After patch 10.2 might will need character transfer for access to BMAH
