Thunderbird

aka Dragonhawk, Fate's Tempest

Flying

Whenever Dragonhawk enters or attacks, exile
the top X cards of your library, where X is the number of creatures you control with power 4 or greater. You may play those cards until your next
end step. At the beginning of your next end step, Dragonhawk deals 2 damage to each opponent for each of those cards that are still exiled.