Well, based on your description of the Dinoceros in the earlier posts, I am telling you that that is exactly what Griffy is, except you can get Griffy by the time Oliver is level 12 if you did the Amazon pre-order. It's totally game breaking. Griffy is a very early riser, so he gets huge stat gains every level. Combine that with the Toto's you can access when you get the boat, and you can get an insanely overpowered familiar after an hour of grinding that I'm sure is gonna last me the rest of the game.
In his first form, by level 11 or 12 I had well over 100 attack, iirc. Moltaan got crushed hard. Right now my griffy is in his third and final form (about level 14 I think) and his phantom fang ability does about 250 damage. I just got to Hamelin. His basic attack does ~120 damage if the enemy is of a weak alignment, or about 70 damage if Griffy's alignment is weak to them.
I'm not sure I want dinoceros, tbh. Sometimes I bench griffy just because with him this game is press X to win.