Hironobu Yoshida

Hironobu Yoshida is a graphic designer who has been involved with several aspects of the Pokémon franchise for many years. Since Pokémon Yellow in 1997, Yoshida has had a hand in the development of the majority of main series Pokémon games, both as a graphic and Pokémon designer. Pokémon he is known to have designed include Wobbuffet, Dunsparce, and several Legendary and Mythical Pokémon such as Celebi, Rayquaza, Deoxys, and Darkrai.

(Source: Bulbapedia)