Acrasidae

A giant creature with multiple blue pits in the middle of its black body. It has the primal urge to absorb anything that moves. In particular, it favors dust, mud, and rot, which it absorbs to thicken its body. A fully grown acrasidae is so hard that most weapons won't be able to even scratch it. It is believed to originally have been a bacteria that multiplied and fused repeatedly to come to its current form.