Undying

Undying is a triggered ability introduced in Dark Ascension. Its function is similar to persist, a keyword ability from the Shadowmoor block; if a permanent with undying is put into a graveyard from the battlefield, it returns to the battlefield under its owner's control. However, unlike persist, a creature with undying returns to the battlefield with a +1/+1 counter on it (rather than a -1/-1 counter) unless it already had one or more of those counters on it when it died.

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