Bio Hunter Silva is an antagonist from Choudenshi Bioman and the true main antagonist of the Super Hero Taisen movie. He is a robot manufactured by the Anti-Bio Union tasked with destroying anything with Bio Particles.
Silva was later rebuilt as a member of Dai-Zangyack to hunt down the Kamen Riders under the title Rider Hunter Silva. However, he later usurps control of the organization and forms an alliance with Dai-Shocker.
During the war on the planet Bio Star, infused with half of the planet's supply of it, Silva was built and programmed to kill anything with Bio Particles. However, Silva follows his objective to the point of using his giant robot to destroy Bio Star before following a trail left by Bio Robo to Earth where he battles the Biomen when being targeted by the Super Sentai's enemies from the Neo Machine Empire Gear as they want to use Balzion.
In the end, Silva was destroyed when Balzion was defeated by a sudden charge of Bio Energy from Bio Robo.
Super Hero Taisen
Rebuilt by the events of Kamen Rider x Super Sentai: Super Hero Taisen as a member of the Dai-Zangyack, a alliance of Super Sentai villains led by Emperor Marvelous (Gokai Red), Silva is given a new objective in the destruction of the Kamen Riders.
However, Silva is eventually revealed to be the true mastermind behind the organization and becomes Dai-Zangyack's leader as his group and Dai-Shocker team up to wipe out both hero types to rule the world.
But, after falling for the Kamen Rider and Super Sentai teams' trap, Silva is destroyed by GokaiGalleon Buster's Tajador Charge when the Gokaigers take the form of Kamen Rider OOO's Combos through Gokai Changes.