Unknown insect-like creatures

Dwelling in a cave the adventurers discovered a couple of large insect-like creatures who attack ferociously.

Information

They seem to dwell only underground and there they work as a collective swarm of some sorts. To build their creeping tumors that slithers across the cavern walls they seem to consume and utilize living creatures. Some acid seems to melt living creatures, successively turning them into a part of the creeping tumors.

Features

• Razor sharp multi-legged creatures who use their spines to attack creatures like an innate spears wielder.

• Across their head and back there is a strange glowing tissue that seems to extend to nearby creatures of the same type.

Variants

• Upon battling these it seems that there are at least four different ones that seems to benefit the swarm in a different way. There are smaller ones (black then at least 3 bigger ones has been sighted; Purple, Blue & Red.