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Rhizome Lurcher is a new card in Guilds of Ravnica that says:
Undergrowth — Rhizome Lurcher enters the battlefield with a number of +1/+1 counters on it equal to the number of creature cards in your graveyard.
It has a ruling that completely surprises me:
If you return Rhizome Lurcher from your graveyard to the battlefield, its undergrowth ability counts itself.
OK, I'm willing to believe that. But why does it count itself? I would have thought that as it enters the battlefield it's no longer in the graveyard and would not count itself. What's going on in the rules for this interaction that have it work out this way?