Early game · first 8 minutes
Hit Rat King with Screwjab Dagger and follow with gunfire. Slide toward cover when Scrap Grenade lands beside you, saving a ground or air dash to remove attached rats.
Vyper vs Rat King
What's giving you trouble?
Full matchup plan
Mid game · Walkers
Apply Lethal Venom after Royal Pestments ends, then shoot Rat King before the venom triggers. It deals more damage as his health falls.
Late game · Patron
Hit Rat King directly with Petrifying Bola while Royal Pestments is active. Attack enemies who are not petrified; Lethal Venom can still damage him while he is petrified, but bullets cannot.