Think of a sorcerer in dnd, it's power comes from pure "talent" so no study required.

Well basicly that, the frog doesn't talk, just answers everything with "croa" but since he is a talented mage and carry a spell tomes, everyone over interpret anything he says as pure genius.

If he was a character in a rpg i would probably make it's weapon to be a book and changing it would only change it's "collar"

A bit of a joke character