Tempering is Diablo 4's new crafting system that allows you to customize your gear. In season 4 and onwards, you can Temper an item at a blacksmith to add two affixes, or stats, onto them using a variety of manuals. Then, you can increase those stats via Masterworking, an endgame crafting system that takes some effort to perfect.
Your items need to be fully Tempered before you can start Masterworking them with materials from The Pit, a new set of endgame dungeons like Diablo 3's Greater Rifts. Masterworking can pump your item's stats way up into the stratosphere, like having a sorcerer's Frost Nova cover the entire screen. With both of these systems, builds will be more flexible, powerful, and dazzling to play.
