Keywardens are four unique demons in Diablo III.
Their name comes from their original role: sometimes, upon death they would drop a key for the Infernal Machine event. As of patch 2.3, they drop Infernal Machines of corresponding type instead.
At levels 61-70, all keywardens have a small chance to drop any level 70 device, which does not compete with their chance to drop their primary machine. This allows any keywarden to drop up to two devices upon death at levels 61-70. At level 60 or higher, they will be marked with a boss icon on the map, and an arrow will point their location.
- Nekarat the Keywarden - Act IV - drops Infernal Machine of Evil (originally, he dropped the blacksmithing plans to create the Infernal Machine, had a chance to drop a random key at level 60, and had a chance to drop Key of Evil at 61-70)
- Odeg the Keywarden - Act I - Infernal Machine of Bones (originally Key of Destruction at level 60, and Key of Bones at 61-70)
- Sokahr the Keywarden - Act II - Infernal Machine of Gluttony (originally Key of Hate at level 60, and Key of Gluttony at 61-70)
- Xah'Rith the Keywarden - Act III - Infernal Machine of War (originally Key of Terror at level 60, and Key of War at 61-70)
As of patch 2.4, their name also shows the material ultimately harvested from bosses in the realms for which they drop their machines.