So, what was Shang's plan?
He was quite sure that he was being watched by some powerful person from the Temple of Blood. However, he couldn't be sure why he was being watched.
Was it a test for the position of Sweeper?
Was it a loyalty test?
Was it a way to make him unveil some of his secrets?
Was his Battle-Strength being tested?
Depending on the answer, it was best to show different things.
If all of this happened simply to test his loyalty, the best course of action would be to take out his Communication Crystal and inform the Keeper that Ice Princess had betrayed them.
Shang wouldn't need to kill anyone, and he wouldn't need to show his power.
Technically, Ice Princess' betrayal was not his problem. He was not a Sweeper.