What you were expecting to happen, and what actually happened?
Dark Priestess spell description indicates that she drains X life from target ally. Accounting for her arcane trait, I expect actual life lost by target ally to be X+1. Instead, two hits are registered on the targeted ally, one for the expected amount (X+1) and a second hit for 1 point of damage.
What are the steps to make it happen again?
Use Dark Priestess’s ability on an ally, observe damage dealt.
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