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Does Dimir Doppelganger trigger ETB (enter the battlefield) effects?
My guess is, that the card doesn't trigger ETB effects, since it's already in play. But the lack of rulings that specify this case make me unsure.
To compare, on Lazav, Dimir Mastermind's gatherer page, the rulings mention ETB effects:
Enters-the-battlefield abilities of the creature card Lazav is copying won’t trigger as Lazav is already on the battlefield when it becomes a copy of that creature card.
Dimir Doppelganger's gatherer page doesn't specify any such ruling. Can I assume it's the same for it as well?