This is an odd one but I’ve confirmed it’s happening in all three places:
- The Mountain Temple boss
- Puppet Master Encore
- bonus Pumpkin 6th Cemetery wave
All of them have a special shot which is aimed at the nearest player every couple of seconds. The MT it’s an animal head which causes unstable, from about 1/2 health. The Encore and Pumpkin it’s just a large shot which causes weak.
They all work similarly in two stages. The shot first moves a square away from the central boss, then shoots in the direction of the nearest player. Except that second aimed shot isn’t happening, the shot simply disappears.
It’s been like this since the last update. I noticed it in MT and the Cemetery, but only just confirmed it happens in the Encore too.