HOW TO DEFEAT ZEUS/ODIN

hey guys ! I need help in defeating Zeus/Odin. The Gengar is a big powerhouse though......so I ned some help! My team is darkrai lvl.90, hawlucha lvl.115, heat Rotom lvl.116, gallade lvl.95 Wailord lvl.103 volcarona lvl.93..Any Help? :)