Sure Strike

Target creature gets +3/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Reckless Lackey

First strike, haste
{2}{R}, Sacrifice this creature: Draw a card and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Ancestral Anger

Target creature gains trample and gets +X/+0 until end of turn, where X is 1 plus the number of cards named Ancestral Anger in your graveyard.
Draw a card.

Unruly Catapult

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap this creature.

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Rodeo Pyromancers

Whenever you cast your first spell each turn, add {R}{R}.

Rakdos Pit Dragon

{R}{R}: This creature gains flying until end of turn.
{R}: This creature gets +1/+0 until end of turn.
Hellbent — This creature has double strike as long as you have no cards in hand.

Run Amok

Target attacking creature gets +3/+3 and gains trample until end of turn.

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Shock

Dual Strike

When you next cast an instant or sorcery spell with mana value 4 or less this turn, copy that spell. You may choose new targets for the copy.
Foretell {R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Mountain

Burning Prophet

Whenever you cast a noncreature spell, this creature gets +1/+0 until end of turn, then scry 1.

Flame-Blessed Bolt

Flame-Blessed Bolt deals 2 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Stoke Genius

Discard your hand, then draw two cards. (Then exile this card. You may cast the creature later from exile.)

Hearth Elemental

This spell costs {X} less to cast, where X is the number of cards in your graveyard that are instant cards, sorcery cards, and/or have an Adventure.