This Was Changed To The First In-Game Tier (Instead Of The Last) To Unlock The Steam Achievement.
- You Must Now Only Dismantle 1 Legendary Item.
You Can Find Legendary Items, Among Other Places, In The Chaos Gate Levels After You Beat The Punika Continent. (ilvl 1100)
Achievement Pops After You Dismantle One Of These In Your Inventory.
Good Luck!