mtg dragons of tarkir collector booster box Dragonstorm - Play Tarkir Dragonstorm Collector Booster Wizards of The Coast Magic:

Against Steelsong decks its invaluable, it shuts down Ursula Deceiver of All singing on turn 4, stops Be Prepared on turn 7, and prevents A Whole New World being sung by Ariel Spectacular Singer

Splinter Twin Two-card combos dont get much more famous than this one

Ozai, the Phoenix King (Rakdos) Yes, the mana cost is heftybut Ozai is the Firebending commander

But creatures in Alpha were dreadful, so this beat stick comes with a very big downside: during your upkeep, you need to sacrifice a creature, or the Lord of the Pit will deal seven damage to you

Eldritch Evolution can play with the tempo, but you can also use it to just find the thing you need when you need it