Why does my monster keep spinning around?

[Strembitsky]

If he spawns in your vision, he will spawn in a specific direction and then have to turn around. When I had this problem, in order for myself to get around it, I just made the monster spawn behind a door in front of me.

Another protip: Don't make the monsters materialize out of thin air.

EDIT: I think I may have read your main problem wrong. Are you saying that he just keeps on spinning, and doesn't stop? Or he spins for a second and then comes after you?