Only as user-created, based on other animals to make things easier (like a reskin of a zebra), otherwise no, just no... The only one of these I'd consider being ok to include are hybrid animals (griffon) like you'd have to breed those two animals - yea good luck with mating big cat and an eagle, that would be interesting. Or we could stick to realistic hybrids like lions + pretty much any big cat, Zebroids, Grolar bears etc.
Anyway... the animals should be realistic or at least a challenge and fun to get, I don't care if they add a few extinct animals either - they existed once. I don't want dinosaurs, but those are far from the only extinct animals on this earth. I'd be very happy if they included the newly extinct animals (in the past 100 years for instance).