In the middle of a gladiator fight, an opponent NPC was engaged in melee and suddenly emoted [looks around, unable to find opponent, and walks away].
Invisibility or stealth was never even used. Not sure what happened, but the emote certainly didn't match the explanation. The fight just ended then and there.
This was not in the Peerage Ward. Some spoilerish stuff involved. Happy to provide more detail (Garem on Discord).