Sword God in a World of Magic

An actual Mage that was an entire Realm above Shang.    

Was this fight winnable?    

No.    

Even if Shang used Fate, his most powerful attack, George would only lose about 20% of his Mana.    

And then what?    

He would just recover that Mana, and Shang wouldn't be able to unleash more attacks.    

The price was clear.    

A way to comprehend the level five Concept of Entropy, Transformation?    

Lucius had comprehended it by sacrificing external Mana, and it took him forever.    

Yet, what was better than experiencing it oneself?    

By experiencing the true power of Entropy himself, Shang could feel what it felt like to turn into nothingness.    

The price?    

Whatever Shang needed to sacrifice from his own body to comprehend the Concept of Transformation.    

That was the price.    

Shang had already sacrificed 15% of his soul to Entropy, and killing George would probably require another 5%, at least.