[quote=VerifyinTr1gIDs]
So, none of the cores seem to fit my character. Either I change it to unicorn, or keep it at my made-up behemoth.
[/quote]

I think that the made-up behemoth should be fine, even if it would be a bit abnormal. You should probably think of some simple magical properties associated with it, though, in case such a subject ever comes up. My first thoughts would be that it might be stubborn, but all-rounded and a little better at outdoorsy activities. That's just me, though~!