They're also showing off a bit of the Sorceress class's special enchanting skill system. In the latest quarterly update, Blizzard are responding to player feedback on earlier updates with some proposed changes to skills, gear, and legendary items. Although Diablo 4 doesn't have so much as a planned release window, Blizzard are continuing to lay out bits of development on the table for players to get a gander at while the studio iterate on the game.
