Kazuma's Alter is called Shell Bullet, an alloy-type Alter which transforms his right arm into a weapon. At its first level, Shell Bullet covers Kazuma's right arm with protective metal armor and creates three curved fins of metal jutting out from his right shoulder blade, each progressively larger as they near his shoulder (only the middle one is the largest one). The fins break apart to propel Kazuma forward at great speed, increasing the power of his strikes, which Kazuma labels as "Bullets". In his second form, Kazuma's arm is completely replaced by a stronger armored arm, four fins of metal jut out of his face near his right eye (actually, they just appear over the skin of his eye, not protruding from it), and a propeller replaces the three fins on his back. This propeller grants Kazuma flight, as well as eliminating the firing limit imposed by his first form. On his fist is a small aperture which can absorb additional Alter power, further strengthening his attacks. In his final form, called "Proud Fist", Kazuma's Alter covers his entire body, causing him to appear as a humanoid cross between a samurai and a lion. His Alter-absorbing fists grow even larger, and his propeller becomes a whip which serves much the same purpose as the fins from the first form or the propeller in the second form.