Early game · first 8 minutes
Send Crow Familiar at Rat King before firing so its bleeding and reduced bullet resistance help you damage him. Keep Stake ready if he runs toward you.
Vindicta vs Rat King
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Mid game · Walkers
Use Flight beside a rooftop or tall cover. When Royal Pestments appears, move out of his sight until it ends, then use Crow Familiar before firing again.
Late game · Patron
Save Assassinate for Rat King after Royal Pestments ends and his health is low. Let the shot fully charge before firing, and keep Stake ready if he advances toward you with the banner.