I looked for something like this, and I couldn't mind anything. Before you say anything about it being "unrealistic", please remember we have primals, snake gods, blue, green, and purple technicolor lions, and a manticore.
Thank you.

I was thinking, you know how in November, the shaman lions are reviving all these extinct species. What if, just what if, they revived one of some primordial beast. Not quite a "primal", as those were all based off of lion-like species. This would be something different (mockup will be made soon, if this doesn't get shot down.) This pantherine beast escapes from the shamans, and roams the jungle, looking for potential lionesses to woo. The lioness is simply charmed by his ancient strength, his rippling muscles, and eventually, things happen, and a new, half-lion, half-beast is born.

I think this hybrid would be introduced in November, and while it can happen year-round, in November, we would have a slight boost of it happening, maybe after a specific encounter (perhaps among the rarity of muk/stellar rem/etc)

Perhaps as a species to use, I was thinking Panthera palaeosinensis
they're pretty cool, and are among the root of the Panthera genus
https://en.wikipedia.org/wiki/Panthera_palaeosinensis
They're generally depicted as having a somewhat heavy, tiger-like build (which is why they were incorrectly thought to be primordial tigers), with a pale yellow
coat, with rosette and stripe-like markings. (of course, this is all just theory)