The Witcher: Covenant Realms

An ordinary contract wizard can carry three or four core contract beasts in his lifetime, which is enough to be called a strong person. Leon discovered that there were still many places in his soul. So—— The Moon Nightmare King Fox left over from the destroyed world. The pure-blooded ancient dragon that burned down the city. A high-level spirit body born from the storm. More and more terrifying beings who were supposed to dominate one side signed contracts with him. Many years later, the war between the worlds broke out. Only then did people discover a very serious problem. Each of Leon's contract beasts can fight a war on its own. And he still has many such contracts.