Using this ability, don't deploy M'Kachan at the start of the game. Instead choose a single model in the army to be M'Kachan in disguise. This may even be an allied model if desired. Once that model suffers a wound, or M'Kachan chooses to reveal himself, remove the model and replace it with M'Kachan. Any damage suffered by M'Kachan while he was disguised still applies.
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