Just a wild guess but the moon, Guwon is probably weaker when the moon is full and the Hound realized it and put two and two together.
Ye but he didn't show any weakness at all
Guwon said in the previous chapter that he’s feeling tired (which seemed to shock him) and he said “that actually hurt”, he probably feels pain and is less than when there’s a full moon or its the one time he could actually be killed.
Do u know crush and burn? If U don't, I am recommending this badly to u. The ml gets more than js headaches when it's a red moon. He becomes extremely vulnerable so I was expecting smth like that. Please read so U will get what I mean.
I feel rewarded. This is exactly what I wanted it to be. Btw how did the hound know they were going to attack? Did I miss sum? At first I thought there was gonna be some crazy twist about guwon.