I Am a Villain in a Parallel World

Parallel Universe No. 20213, This universe is full of aura. Humans here have been fighting against a creature called an armored beast for hundreds of years. At first, humans fought with the armored beast and were completely crushed by the armored beast. Until a few humans obtained the energy crystal of the armored beast, these humans relied on it. He started practicing with the Armor Crystal, and later discovered that the Armor Crystal could transform into armor, but it was extremely unstable. Hundreds of years later, humans invented technology that could stabilize the Armor Crystal. Finally, the crushing relationship between humans and Armor Beasts reached a balance, and this technology was called the Summoner.