Seems like those two mobs above somehow is able to spawn on the volcano structures from Alex's caves

here's the pastebin https://pastebin.com/2bQtUtm9

I'm pretty sure this bug is also what's causing alot of performance issues in the primordial cave itself, and i suspect it also decreases the amount of endemic mobs spawns.

Ortoises and Stonelings have gotten a little carried away with spawning. Maybe they learned how to multiply!