Basilica Screecher

Flying
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Augur of Skulls

{1}{B}: Regenerate Augur of Skulls.
Sacrifice Augur of Skulls: Target player discards two cards. Activate only during your upkeep.

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

This spell costs {3} less to cast if a creature died this turn.
Flying, deathtouch

{T}, Sacrifice Liliana's Steward: Target opponent discards a card. Activate only as a sorcery.

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Sacrifice Fume Spitter: Put a -1/-1 counter on target creature.

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

You may pay {1}{W} and exile a creature card from your graveyard rather than pay this spell's mana cost.
Flying

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.