Gu Master and Nano Doomsday

As soon as the Kangping people returned home, the apocalypse broke out. "Be lenient if you confess, be harsh if you resist..." "No, sir. Is it the end of the world outside?" "Given your special entry method, I have reason to suspect that you are an accomplice!" "..." "Sir, I'll do it, I'll do it all! I'm a gray Gu master, but I'm really forced!!!" "Very good, let's go north!" Kang Ping follows this southwest nano-response team through the southern region where the gray goo crisis is raging. Conquer the rioting nano-devouring Gu insects along the way and try to save this country and even all mankind.