Great Emperor Zero

Great Emperor Zero (ゼロ大帝): A who poses for the real Zero, using his lance to execute traitors and failures alike. When Amazon arrives to Garanda's base, Zero negates the GiGi Armlet's powers with his lance as the Helium Bomb is installed. However, once the GaGa Armlet is fused to the GiGi Armlet, Amazon become immune to Zero's power as he loses his arm to the Kamen Rider before he gets impaled by his own pit trap.

Background
Great Emperor Zero is the title of those who inherited three sacred treasures of the Garanda Empire's ruling Zero House (ゼロ家): the Helmet of Flaming Wings (火の翼のかぶと), the Blood Cloak (血のマント), and the spear Blue Thunder (青い雷). The current Great Emperor Zero was said to have been born in 1938, and aged 37 when he was slain in 1975.

The legendary ruler of the Garanda Empire, Great Emperor Zero asserts his claim of descent from the ruling dynasty of the ancient. He wears a helmet with a flaming decoration while his body is guarded by steel armor. A very cruel man, Zero does not hesitate to execute unsuccessful Beastmen and Kurojusha with a sparkling high voltage beam from the Blue Lightning spear.

Biography
to be added

Kamen Rider Spirits
In the manga Kamen Rider Spirits, "Great Emperor Zero" transplanted Daisuke Yamamoto's left arm with a GiGi Armlet and became an Amazon.

Kamen Rider SD: Sortie!! Rider Machines
Great Emperor Zero appears as the fourth boss at the end of the fourth stage. He appears in a rocket powered walker mecha and fires his machine gun at V3 while trying to side swipe the Hurricane. Using defensive powerups to hit him at a distance or dodge his gunfire and kick the mech and it will eventually whittle down his armor and destroy the walker mecha.

S.I.C. Hero Saga
In an alternated timeline which the ten veteran Showa Riders were erased by an unknown power, when Great Emperor Zero was decapitate by Ruler in front of Kamen Rider Hibiki, it was revealed that the true identity of this fake Emperor Zero is actually always Salamander Beastman, who imitated the Ruler's appearance as the political decoy.

Portrayal
Great Emperor Zero is portrayed by Hirohisa Nakata (中田 博久) who previously played the titular character of Captain Ultra and would later play in the 1984 Super Sentai series .

Conception
Great Emperor Zero's design is based on a knight of Medieval Europe, recalling the Spanish Conquistadors who conquered the Incan Empire in what would become the home of Amazon.