Two hundred years ago, on the Battlefield of the Blue River, the last remaining army of the Empire of Light collapsed in the midst of demonic outcries. As the last Field Marshal and Emperor fell, the chaotic world of the Western River no longer had a common ruler. Factions were formed and endless conflicts ensued, military might became the only currency of survival, and the dream to reunite the lands became the sole goal of many rulers in the generations that came after. In the south-eastern part of the land, a powerful faction with over two hundred years of history – House Zichuan – fought off the Demons to the east, defended against the House Liufeng to the west, and contained the House Lin to the south. In order to accomplish their great ambitions and extend the bloodline of their family, countless heroes of Zichuan gave their lives in order to make this magnificent hymn come to life. This is a story about this legendary family and a hundred years of their blood and tears.

For millennia, the ancient and mysterious Dragon Clan has thrived on the Central Continent. Yet the struggle between the Light and Dark Souls of the Divine Realm drags the dragons into conflict. The clan is torn apart by brutal civil strife, facing the threat of extinction. In this desperate hour, Ao Xue, the long-absent prince of the East Sea, returns with formidable power, determined to save the Dragon Clan from peril.

A thousand years ago, the divine general Fei Peng and the Demon Sovereign Chong Lou engaged in a fierce battle in the New Immortal Realm. The divine sword "Zhao Dan" fell to the mortal world, and Fei Peng was demoted to earth. A millennium later, the Lock Demon Tower of Shu Mountain trembled, and Fei Peng's reincarnation, Jing Tian, who obtained the demonic sword, embarked on an adventure alongside Tang Xuejian, Xu Changqing, and Zi Xuan to collect the Five Spirit Orbs and seal the Lock Demon Tower.

Ren Homura has just moved back to his hometown of Kaminohara, but he is not able to remember much about the time he spent there other than vague flashbacks. When he retrieves his cell phone which he had sent to a shop for repairs, he finds that a mysterious game titled "Monster Strike" has been installed on it. Unaware of its purpose or how it got there, Ren decides to open it, an action that will change his life forever as he finds himself suddenly attacked by a strange man. Now trapped on the roof of his school which strangely has been designated as a "stage," Ren is shocked to see the man summon a realistic monster from the game, one that is more than capable of inflicting damage on a human. His only chance of getting out of this situation alive is by summoning the dragon Oragon, who tells Ren that he will crush the opposing monster for him. Unfortunately, it turns out that Oragon is a tiny dragon that is completely useless!