How the New Summoning System Works: Bosses are now free to Diablo 4 Items summon, removing the need to grind materials. Instead of dropping loot directly, bosses will drop a Hoard Chest. To open the chest, players need a Lair Key, which replaces the old summoning materials. Every player in a party must have their own Lair Key to open their chest. Blizzard introduced this change after player...