Liquid Fire

As an additional cost to cast this spell, choose a number between 0 and 5.
Liquid Fire deals X damage to target creature and 5 minus X damage to that creature’s controller, where X is the chosen number.

Traumatize

Target player mills half their library, rounded down.

Shifty Doppelganger

, Exile Shifty Doppelganger: You may put a creature card from your hand onto the battlefield. If you do, that creature gains haste until end of turn. At the beginning of the next end step, sacrifice that creature. If you do, return Shifty Doppelganger to the battlefield.

Seize the Day

Untap target creature. After this main phase, there is an additional combat phase followed by an additional main phase.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Vivify

Target land becomes a 3/3 creature until end of turn. It’s still a land.
Draw a card.

Howling Gale

Howling Gale deals 1 damage to each creature with flying and each player.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can’t be blocked as long as defending player controls an Island.)

Arden Angel

Flying
At the beginning of your upkeep, if Arden Angel is in your graveyard, choose a number from 1 to 4 at random. If the chosen number is 1, return Arden Angel from your graveyard to the battlefield.

Dead Ringers

Destroy two target nonblack creatures unless either one is a color the other isn’t. They can’t be regenerated.

Bloodfire Colossus

, Sacrifice Bloodfire Colossus: It deals 6 damage to each creature and each player.

Emblazoned Golem

Kicker (You may pay an additional as you cast this spell.)
Spend only colored mana on X. No more than one mana of each color may be spent this way.
If Emblazoned Golem was kicked, it enters the battlefield with X +1/+1 counters on it.

Zombie Boa

: Choose a color. Whenever Zombie Boa becomes blocked by a creature of that color this turn, destroy that creature. Activate this ability only any time you could cast a sorcery.

Bloodfire Kavu

, Sacrifice Bloodfire Kavu: It deals 2 damage to each creature.

Sunweb

Defender (This creature can’t attack.)
Flying
Sunweb can’t block creatures with power 2 or less.

Squall

Squall deals 2 damage to each creature with flying.

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can’t be blocked as long as defending player controls an Island.)

Seismic Assault

Discard a land card: Seismic Assault deals 2 damage to any target.

Mana Short

Tap all lands target player controls and that player loses all unspent mana.