Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Bonesplitter

Flying
When Owl Familiar enters, draw a card, then discard a card.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Jeskai Sage dies, draw a card.

When Floating-Dream Zubera dies, draw a card for each Zubera that died this turn.

Counter target spell unless its controller pays {1}.

Flying
When Skyscanner enters, draw a card.

Equipped creature gets +1/+0.
Whenever equipped creature dies, you gain 3 life.
Equip {1}

Flying
When Surveilling Sprite dies, you may draw a card.

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Shadow (This creature can block or be blocked by only creatures with shadow.)
When Thalakos Seer leaves the battlefield, draw a card.