It's a killer whale (Orca). Just a mesh and a texture. No rig. Uploaded new version because I forgot to add a blow hole! :o
I was also modeling an orca, but this one is awesome, very lowpoly and very well done, despite some minor anatomical licenses.
i could imagine sonic being like: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA