Nesting Dovehawk is a rare Creature — Bird card from March of the Machine Commander (MOC), collector number 17. Current market price: $23.11, TCGplayer market prices via Scryfall.
Flying At the beginning of combat on your turn, populate. (Create a token that's a copy of a creature token you control.) Whenever a creature token you control enters, put a +1/+1 counter on this creature.