"Combat Fairy System"(CFS) A portable AI combat assistance system developed by "Yunding" company. It can provide shield defense and tactical support for the wearer. In order to promote, the company also held a competition to show the "performance" of its products. In pursuit of high prize money, a large number of "gladiators" flocked to it. One day, Bai Ye, who was wandering on the street, met a girl, Chi Jin, who could transform into a CFS weapon. For their respective purposes, Bai Ye and Chi Jin formed a partner and participated in the fight in the arena together. The battle is based on half real-time strategy, using various tactical cards collected in the game to defeat the enemy. The defense in the game is centered on the shield mechanism, which can be immune to most negative effects, while the offense can use the five elements mutual generation and mutual restraint mechanism to kill the enemy more efficiently. Using the five elements rule to break the enemy's shield as soon as possible will be the key to the battle.