I don't have much to say about charizard really. I admit that I have a slight problem with tetrapods with six extremites, such as most dragons, griffins and pegasuses. I just can't help it
(I don't dislike them in any kind of way, they just puzzle me so to say)
But I image that the horns and faned tail help charizard to steer and manuver better when flying.
I think charmelon and charmanders use their faned tail (and horn for charmeleon) to keep the banace when they run, I image them to be some kind of quick, raptor-like creatures.
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