Early game · first 8 minutes
Shoot Mo & Krill as they approach underground; damage reduces Burrow’s speed bonus. Keep enough distance to dash away before they surface.
Rat King vs Mo & Krill
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Mid game · Walkers
Keep Royal Pestments for the damage after they surface. If Sand Blast disarms you, use Scrap Grenade and Rat Swarm while your gun is disabled.
Late game · Patron
Slam your banner down to interrupt Combo when Mo & Krill catch a teammate. Spread out so Burrow cannot knock up several allies when they surface.