Slow Foot and Headless Horror, respectively known as Single Foot (シングルフット) and Born Head (ボーンヘッド, sic, "Bone Head") in Japan, are the weakest enemies in Altered Beast, slow moving zombies that are worth 100 points each. They are more common in the first stage.
Slow Foot simply moves forward until it touches the Centurion, then starts flashing and explodes. Sometimes a Slow Foot may come out from Tombstones.
Headless Horror is a zombie that holds its head in his arm and attacks by punching.