Breaking NPCs and Spider Queen appearing for a few frames

The Video:
It works on other NPCs if you’re too lazy to watch it.
Spider Queen randomly spawns and disappears at 5:20, 5:45, and 6:15. I’m too lazy to check for more. Put it on 0.25 speed to see it for like a frame. Sorry for low quality. I was using the Roblox recording thing.

know glitch, a loading bug.

Both bugs are known, the spider queen one is a monster book glitch and can happen to any mob in the monster book. also is that an ad I see in the video? HMM