The Robot Halfbody (ロボットハーフボディ, Robotto Hāfubodi) is an abiotic B-Side Halfbody of Kamen Rider Build. Accessed through the Robot Fullbottle, its Best Match is the Phoenix Halfbody. Machinery Head Armor (マシナリーヘッドアーマー, Mashinarī Heddo Āmā) - The gunmetal gray head armor. A thick metal-like material with excellent durability is used in its composition. Since the surface layer is covered with a liquid similar to mechanical oil, it can also prevent attacks that can cause corrosion and rust effects. R