From ONUV, on Team Village
Depending on the other roles used in the game, it may or may not be advantageous for the Priest to cleanse another player (since this action is optional). It is disadvantageous to cleanse another player if there is a high chance of cleansing a Vampire of the Mark of Love or Mark of the Traitor. It can be advantageous if there is a high chance of cleansing a Vampire of the Mark of Disease or cleansing a Villager of the Mark of the Vampire.
It is not advantageous for the Priest to announce who he cleansed until he finds out what mark that player had previously. Assuming the Mark of Love, Mark of Disease and Mark of the Traitor have already been accounted for (i.e. were not cleansed) and any apparent cleansing has not replaced the Mark of the Vampire, Team Vampire may think the player they gave the Mark of the Vampire to still has it. The Priest would do well not to correct this erroneous belief. Team Vampire may think they have a majority, particularly if Renfield is in play. Once Team Vampire confidently announce their majority, the Priest can announce that in fact they they cleansed the Mark of the Vampire from someone else and the Vampire minority just revealed themselves for certain defeat.
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