"Pure fire" refers to the smelting process, when the temperature of the fire reaches more than 3,000 degrees Celsius, the gas in the furnace will be gradually discharged, leaving pure oxygen, at this time the flame shows a green color, which is known as "pure fire". "This idiom is used to describe a person whose skill has reached a very high level of proficiency, just as the fire has reached a state of pure green.

The idiom of "out of the gods into the realm" describes a person's skill that has reached a very high level, like entering the realm of the gods or reaching the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the realm of the gods. very wonderful".