Enigma chamber bug

I just got to the Eastern enigma chamber got to the end and beat the boss.

For starters no loot dropped which I thought was a bit weird, but secondly the lightning attack that follows you around the chamber was still active even though the boss was dead.

I thought “I’ll just jump through the portal then” but it followed me and nuked me in the next room before I could move

Returning to town didn’t help - it was still there and followed me through the portal every time

I’ll try running it again but it was rather annoying