Dark Petition

Search your library for a card, put that card into your hand, then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, add {B}{B}{B}.

Thud

As an additional cost to cast this spell, sacrifice a creature.
Thud deals damage equal to the sacrificed creature's power to any target.

Mr. Orfeo, the Boulder

Whenever you attack, double target creature's power until end of turn.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Behold the Beyond

Discard your hand. Search your library for three cards, put them into your hand, then shuffle.

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Mastermind's Acquisition

Choose one —
• Search your library for a card, put it into your hand, then shuffle.
• Put a card you own from outside the game into your hand.

Exponential Growth

Until end of turn, double target creature's power X times.

Burn Together

Target creature you control deals damage equal to its power to any other target. Then sacrifice it.

Callous Sell-Sword

Callous Sell-Sword enters with a +1/+1 counter on it for each creature that died under your control this turn.

Callous Sell-Sword // Burn Together

Become Immense

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Target creature gets +6/+6 until end of turn.

Balduvian Berserker

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
When Balduvian Berserker dies, it deals damage equal to its power to any target.

Gravitic Punch

Target creature you control deals damage equal to its power to target player.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Unleash Fury

Double the power of target creature until end of turn.

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.