Early game · first 8 minutes
Build Fixation with short bursts of gunfire from cover. If Rat King throws Scrap Grenade at you, move before firing again.
Haze vs Rat King
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Mid game · Walkers
Use Sleep Dagger after Royal Pestments ends. Reload or move closer while Rat King is asleep, then fire with your teammate.
Late game · Patron
Wait for Royal Pestments to end and for Rat King to slam his banner down before using Bullet Dance on him.