It seems they are changing and not following the novel. I would have really liked the giant monarch scene
He surely did get involved in the light novel. The ants getting on China is what I believe one of their topics on their first meeting on an event (●'◡'●)ﾉ
No that's the thing with the giants (that came out from the Japan gate) that caused the catastrophe over there before Jin-Woo stepped in. In fact, in chapter 196, the Chinese guy said to Jin-Woo that he was surprised by how strong just 1 of those creatures were (giants) and that it was difficult to fight it on the ocean surface (He says specifically "Giant monster" which is the monster from Japan since everyone refers to the ants as just ants).
I don't have enough time right now to go back and check if he was ever seen before the Japan incident but I'm 70% sure that he never appeared before then. Even in the giant incident in Japan, it was mentioned in the novel in a couple of lines that one giant escaped and he took care of it and his first official appearance was in the event in the US. Even on wiki (not the most reliable but gives us a general idea), it says that his first appearance was in chapter 185 https://solo-leveling.fandom.com/wiki/Liu_Zhigang#History
nah i think they added liu killing ants in the webtoon. liu zhigeng dealt with one giant in china and that’s all i think
CONTAINS SPOILERS
I don't remember that the Chinese National Level Hunter showed up in the novel at this point and I don't remember ants getting to China. I thought that happened later when the gate opened in Japan and Jin-Woo defeated all the monsters but 1 that managed to escape to China and then the Chinese guy defeated it and he mentioned that when they all met in America.
Did this happen in the novel and I just forgot about it?