Book Burning

First strike (This creature deals combat damage before creatures without first strike.) When this creature enters, you gain 1 life for each card in your graveyard.

Creatures you control get +0/+2 until end of turn. Threshold — If there are seven or more cards in your graveyard, choose a color. Creatures you control also gain protection from the chosen color until end of turn.

Create two 1/1 white Bird creature tokens with flying. Flashback—Tap three untapped white creatures you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Flying Threshold — As long as there are seven or more cards in your graveyard, this creature gets +1/+1 and has first strike.

Sacrifice this creature: Target creature you control gains protection from the color of your choice until end of turn.

Vigilance

Enchant creature Enchanted creature gets +2/+2 and can't attack.

Destroy target enchanted permanent.