Bayleon, a pokemon once thought to be extinct; It's psychic powers and charm were rivaled by none, and no trainer could hope to claim the prize of it's capture. Legends, tell however, of a terrible curse, inflicted on only a few rare specimen; a curse that is, for the most part, unknown. All that is certain is that the moon's passage has something to do with this curse, and that the results are not meant for eyes of mere mortals....
First, attempting to reproduce with a Bayleon without its explicit consent is a good way to get your pokemon murdered brutally. Second, the biochemical makeup of the Bayleon rejects pokeballs by nature, in the same way that prevents humans from being captured.