|This article is about a/an event in Choudenshi Bioman.|
The Bio Civil War (バイオ星戦争 Baiosei Sensō) was an event which occurred on the planet Bio 500 years prior to the beginning of Bioman's battle with the Neo Empire Gear on Earth. The event lead to the destruction of planet Bio and the emergence of its factors in and around Earth that would affect Bioman's battle.
500 years prior to the beginning of Bioman, the planet Bio existed as a peaceful planet in the galaxy. The planet was notable for its advanced scientific knowledge and skills to advance the standard of living and way of life of the people who live on the world. Around this time, a faction of scientists on the planet known as the Bio Peace Union made a discovery that would change everything: a particle that could allow for the usage of a great power that would be able to improve all those who partake in it, including humanoids and machines. The new particle would be given the name of the Bio Particle and it should have been the dawn of a new era of peace and prosperity for the planet.
However, there were those on the planet who did not trust or believe in the power that the Bio Particle presented. These people and scientists believed that the particle would only endanger the planet and that they needed to fight back against the potentially dangerous effects of this new science. These scientists would form a rival faction against the Bio Peace Union, known as the Anti-Bio Union and would work to develop a means to combat the potential danger of Bio Particles. Ultimately they devised an antithesis particle meant to destroy Bio Particles and prevent them from causing harm and to combat them: Anti-Bio Particles.
With the new power in their hand, the Anti-Bio Union went to war with the Bio Peace Union to defeat and destroy their new technology that would possibly bring harm to the planet. The two sides fought for years and many casualties were created. Both sides would continue to develop new technology that would allow for Bio and Anti-Bio elements to combat the other side, hoping to have the ultimate edge that would allow for victory in the war. Ultimately the Bio Peace Union devised an ultimate weapon to fully utilize the full power of Bio Particles to their maximum: Bio Robo, a giant robot empowered by Bio Particles gaining sentience through their usage to allow for it to work alongside Bio Particle warriors in combatting their enemy. Unfortunately, the Anti-Bio Union likewise devised their own ultimate giant machine: Balzion, empowered by Anti-Bio Particles and meant to be the ultimate weapon to defeat Bio Robo in combat. Going one step further, the Anti-Bio Union also developed an ultimate machine warrior to both combat Bio Particle warriors and pilot Balzion: a silver-colored robot warrior by the name of Bio Hunter Silva. Silva's whole purpose is to find Bio Particles and destroy them, using both his own Bibuster gun and the Balzion mecha to destroy everything he sees as a Bio Particle threat.
Ultimately, the war of the two Bio factions paid a heavy toll on planet Bio. A combination of the combat and the unintended consequence of Anti-Bio Particles in causing greater damage and destruction to anything they touch, not just Bio Particles, the planet decayed into ruin and ultimately became too unstable to last for very much longer. Knowing that the planet was doomed due to their civil war, the Bio Peace Union chose to send Bio Robo to another world to protect it in case it would be needed again: a paradise planet they knew of as Earth. Alongside Bio Robo, the faction also sent Peebo, a robot assistant produced to assist in Bio Particle experiments, to work alongside the weapon and to help whomever on the planet ended up working alongside it. However even as Bio Robo was safely transported off the world, both Silva and Balzion traced the machine's departure and pursued them through space. However, the Anti-Bio machines became separated during this period; with Silva ultimately spending the next 500 years searching for Balzion while moving to eradicate any remnant Bio Particles it could track down; while Balzion secretly crashed into a ravine likewise on Earth hidden away in secret from those that could use it.
In the end, the planet Bio no longer could survive due to being worn down by war and Anti-Bio Particles and was destroyed, with only the rival war weapons being the remaining remnants of the cruel, destructive conflict.
Although Bio was destroyed by the Bio Civil War, its legacy remained due to the survival of the machines associated with the conflict; both Bio Robo and Peebo as well as Balzion and Silva. Bio Robo ultimately does make its way to Earth, where it would quickly grant the bloodline of five humans in Japan the means to use the powers of planet Bio should the need occur. The five ultimately were the ancestors of the modern day Bioman, who would ultimately join with Bio Robo and Peebo in order to combat the Neo Empire Gear with their emergence. Unfortunately the legacy of the Bio/Anti-Bio battle would come to haunt the Bio Particle-enhanced warrior, both in Silva and Balzion becoming wild cards in their battle with Gear as well as giving greater knowledge of Anti-Bio Particles to Gear's leader Doctor Man, who would successfully use the information to create his own war weapons as well as to kill one of Bioman's members with them. Only with the defeat of both Silva and Gear would the legacy of the Bio Civil War ultimately come to a close.