Evolve is a keyword ability.
- 702.99a Evolve is a triggered ability. “Evolve” means “Whenever a creature enters the battlefield under your control, if that creature’s power is greater than this creature’s power and/or that creature’s toughness is greater than this creature’s toughness, put a +1/+1 counter on this creature.”
- 702.99b A creature “evolves” when one or more +1/+1 counters are put on it as a result of its evolve ability resolving.
- 702.99c A creature can’t have a greater power or toughness than a noncreature permanent.
- 702.99d If a creature has multiple instances of evolve, each triggers separately.