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If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on it instead.
If a creature you control would enter the battlefield with a number of +1/+1 counters on it, it enters with twice that many instead.
If you control two Corpsejack Menaces, the number of +1/+1 counters put on a creature is four times the original number. Three Corpsejack Menaces multiplies the original number by eight, and so on.
