Rule 702.156a

Ravenous is a keyword found on some creature cards with {X} in their mana cost. Ravenous represents both a replacement effect and a triggered ability. “Ravenous” means “This permanent enters the battlefield with X +1/+1 counters on it” and “When this permanent enters the battlefield, if X is 5 or more, draw a card.” See rule 107.3m.

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