I'm having 15 to 40+ friendly monsters spawning every zone and I have no idea why

There are three different types and they are popping up everywhere. They don't follow me, but just walk around near their spawnpoint attacking enemies that are close. They all stick around until they are killed or the zone resets. I also can't find any info about them being anything other than hostile monsters online.

Skullslinger


Spinesnatcher


Ribrattle

I don't know if this is a bug, but the thread was moved here. I've been these guys for maybe 6 hours of gametime across several days and several acts IIRC.

EDIT: I've been told it might be getting summoned by my spectre from the wildwood. I hadn't thought of it because the spectre is a dual wielding melee fighter, and I've been seeing the minions since before I picked him up. However, the most past spectres I've been using are casters from the same "tribe" as my current one.

The spectre in question (to the right)