After completing the hero point in the swamp, I moved up onto the Temple of the Ages platform and spoke to a Tortured Spirit there, thus summoning a Shade – The Veteran Marsh Drake guarding the hero point wiggled up onto the platform after me.
To my surprise, they both attacked the Tortured Spirit who did not fight back.
After it died, the Tortured Spirit immediately respawned as a Wrathful Spirit.
It slaughtered the Shade, and the Shade also instantly respawned as a Wrathful Spirit.
The Shade Spirit ended up dying and did not respawn – the other one turned and started carving up the Drake.
The Drake won, the ghosts stopped respawning, and I found I had somehow completely lost aggro.
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