Ornithopter

Faerie Impostor

Flying
When Faerie Impostor enters, sacrifice it unless you return another creature you control to its owner's hand.

Spell Queller

Flash
Flying
When Spell Queller enters, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Barrin, Tolarian Archmage

When Barrin, Tolarian Archmage enters, return up to one other target creature or planeswalker to its owner's hand.
At the beginning of your end step, if a permanent was put into your hand from the battlefield this turn, draw a card.

Incursion Specialist

Whenever you cast your second spell each turn, Incursion Specialist gets +2/+0 until end of turn and can't be blocked this turn.

Niambi, Esteemed Speaker

Flash
When Niambi, Esteemed Speaker enters, you may return another target creature you control to its owner's hand. If you do, you gain life equal to that creature's mana value.
{1}{W}{U}, {T}, Discard a legendary card: Draw two cards.

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.