The Final Axe is a incredibly powerful, yet rare, two-handed weapon. It is suitable towards Warriors and Paladins, or any others with a high Attack Rating. It provides lethal bonuses, and can be given to a Power Core Dealer for 100 
, or with 95 Runeforging to create a [Final Axe of Power] .
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The Final Axe drops from some of the more powerful monsters over Level 65. The chances of getting one are slim, around 2%. Elite creatures tend to carry these weapons around as well as a drop. It is also a reward choice for the Quest: Known Tools.
Another way is to kill someone in a staked duel or the Nether Realm who is carrying it.