The Angered Dead
From Diablo Wiki
The Angered Dead is triggered when Ghostly Masons and Shadow Swordwielders are encountered in the Westmarch Commons in Act V. The initial objective of this event is to investigate the Brenden Manor Grounds. This is a circular place with a central fountain. Upon entering Brenden Manor Grounds, Lord Darius Brenden, a superunique human, appears and the two entrances gates close, preventing your escape. The objective now is to kill Lord Darius Brenden who constantly spawns Shadow Swordwielders. Note that if you keep killing the Swordwielders, Lord Darius Brenden eventually gives up spawning his minions.
Dialogs during The Angered Dead event
When trapped in Brenden Manor Grounds
Lord Darius Brenden: "No one enters my grounds uninvited! Die, peasant!".