I thought I’d make a report for this because this is happening ALOT lately. If you throw your decoy and it is spec’d into sonic wave to fear mobs, alot of the time one mob will get feared into a wall and get stuck. Then when you’ve finished your 5 waves, you have to run around the edge of the arena to find the one mob that is stuck in the wall.
Probably a known issue but I’ve been seeing it happen ALOT lately in my arena runs.