
I've thought about treating them like a "magic item," but this seems a little outside of PC control - if my character wants to ride a griffon, and wants to take class features that reasonably assure that, that should be okay. Medium only, and the critter needs to be weak.

The closest mechanic in the existing game is the ranger's animal companion and, let's face it, that's not gonna cut it. The question is: how? How to do it in a reasonably balanced way? The goal here is to give a character a friggin' monstrous creature, loyal to them, that they can ride around on and fight alongside.
