Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Iron Myr

Red Dragon

Flying
Fire Breath — When this creature enters, it deals 4 damage to each opponent.

Run Amok

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

Bulk Up

Double target creature's power until end of turn.
Flashback {4}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Mountain

Ruby Medallion

Red spells you cast cost {1} less to cast.

Crackle with Power

Crackle with Power deals five times X damage to each of up to X targets.

Teeterpeak Ambusher

{2}{R}: This creature gets +2/+0 until end of turn.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

The Reaver Cleaver

Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens."
Equip {3}

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.