Item:Thread of Fate

Legendary Soul is an end-game raid currency introduced in Update 41 as an incentive for players to run a variety of raids at cap, rather than just the few they specifically want gear from. Legendary Souls are.

Usage
As of Update 41, their main use is to turn old at-cap raid gear into new and improved versions. In the future, they will be used for a variety of things, such as upgrading future raid gear or acquiring raid-level items.