Dr. Xeno Houston Wingfield (Dr.ドクター ゼノ・ヒウストン・ウィングフィールド Dokutā Zeno Hiusuton Wingufīrudo) is a scientist and the former leader of the American Colony, and currently one of the leading scientists for the Kingdom of Science. Xeno is the main antagonist of the New America City Arc and an uneasy ally of Senku's in the South America Arc, later becoming a proper ally in the New Stone World Arc.