Turtle/Simurgh hybrid ($10)

Is he a mutant? Is he a yokai? Who the heck knows lol 

He is, in fact, a mutant 

He's an asiatic softshell turtle mixed with the simurgh thing from rottmnt

This little guy was was an aftermath experiment. Baron tried to use some bird dna to make "an avian turtle hybrid warrior" but after Lou escaped and the lab collapsed, Baron put his experiment into stasis and basically just left him in the lab

But while the lab was collapsing, the stasis tube was damaged, allowing the hybrid to age albeit very slowly. He wasn't found again until sometime after the first episode, when Raph and Donnie returned so Donnie could salvage some of the tech

If this sounds dumb then y'all can fight me :)