Diablo® III

Invulnerable minions will sometimes not lose their invulnerability even when their leader is killed. It's more or less a map reset on the later difficulties.

Had this issue with a pack in the Storm Halls. Two of the minions came up out of the ground, attacked with their leader, and died after the leader died. Two minions stayed in the ground,, then popped up to fight after the leader was dead. They remained invulnerable

Edit: Spent about 10 mins in other parts of the dungeon and they despawned. Also took a death before going back to the invuln minions' location

same issue here in act 1 hell difficulty

Same issue, killed the boss but didint affect on minons anyhow. Hell difficult act2 Cave of the Betrayer lvl2.

Had this issue as well. Happened to me because I killed the leader of the pack far away from the minions