It is revealed in Sins of the Father that Kroy was responsible for the second outbreak of the Sleeper Plague, having discovered the original formula to the Elixir of Everlasting. He was then tasked by his superior, Damien Leucurte, to distribute the formula via Bloody Bracer, the town's local drink. The player then confronts Kroy after the conversation and kills him, before destroying his lab.
Kroy can be safespotted behind the two northern tables using magic or range. Head north to the two tables and Protect from Magic to make this fight easier.
Kroy will occasionally throw a vial that weakens you if you don't move out of the way. The animation is different from his regular attack; watch for a vial appearing in his hands. It's also visible in the air, meaning that safe-spotting will allow you to see it and move out of the way. After the vial is thrown, provided it does not hit you, a puddle will appear on the floor that will also weaken you if you walk over it.
He will switch between magic and melee — whichever you're not praying. If you are praying magic, Kroy will try to melee you if you are within melee range; if not, he will use magic.
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