"What manner of foul creature is this?" Viktor exclaims, looking at the horrific scene unfolding before the party. "No matter. It is foul, and must be purged!"

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Detect Evil on the troll. If it is evil (assuming it is), declare a smite evil. If it isn't, don't. Ready an action to move and power attack when it charges (as Oh My God's OOC plan).

Power attack roll: (1d20+9)[20]
Damage roll: (1d10+7)[11]

Status:
HP 12
AC 22