FrozenSol worked on the Manticore. He fixed the model and animation (the original animations were flawed, the horns were clipping through the body, and the wings were awkwardly positioned. FrozenSol has already fixed this), as far as I understand, the Manticore is almost ready for him, I don't know why he isn't releasing it, maybe he just hasn't had time to fix the last minor details, or maybe something else. He seems to have decided not to create an improved Manticore.
I'm saying this because, Footman, if you decide to work on the Manticore, I don't think it makes sense to do work that someone else has already done. It might be wiser to collaborate with FrozenSol and combine efforts.