Koumei

Komei, known by the titles "Genius Tactician" and "White Feather", is the main antagonist of the Adventure of Nebulandia special. He first appeared as a member of the Foxy Pirates, but in reality, he is a Vice Admiral of the Marines that went undercover. He is a special operation adviser from the Strategies/Tactics Research and Development Division of the Marines.

(Source: One Piece Wikia)