Staff Officer Steel (鋼鉄参謀 Kōtetsu Sanbō?, 27-29): An armour monster who has great strength which surpassed Kamen Rider Stronger. His weakness is Doctor Kate's poisonous gas. Destroyed by Stronger's Stronger Electro Kick.

Kamen Rider Decade: World of Stronger

Staff Officer Steel appeared in World of Stronger fighting against Kamen Rider Decade, but it he's been defeated.