Jolrael, Voice of Zhalfir (Buy-A-Box) [March of the Machine: The Aftermath]

At the beginning of combat on your turn, up to one target land you control becomes an X/X green and blue Bird creature with flying and haste until end of turn, where X is the number of cards in your hand. It's still a land.

Whenever a land creature you control deals combat damage to a player, draw a card.