Knowing the weakness of a beast was always the best way to go about fighting one. Especially when it came to fighting one that was stronger than you. However, Clark knew that this was not a simple beast.
a beast would follow reason. It would have left this temple when it was able to. It would have found a way to leave to find a better place to live. It would have done whatever it could so that it would be able to survive.
That was where things became different between beast and a monster.
This was a monster. It looked for the best place to hide itself when it needed to. It used whatever means to grab at food when it needed. It went wild and ignored its own pain and suffering to cause that to others. A monster was everything wrong with what people would see when they thought evil.