An Ink Storm Rodent (インクストームげっ歯類, Inkusutōmu gepparui) is an untyped rat that is entirely black. It's think fur is all made of black ink, making them more noticeable than their slime storm counterparts. As a last resort during a heated battle, it wringes out as much ink as it can in the hopes of getting it in their predator's eyes.
Due to my lack of skill in drawing, i can't exactly show you what it would look like.