Cloud Manta | Creature | Fish | Flying | Mike Bierek
Coralhelm Guide | Creature | Merfolk Scout Ally | {4}{U}: Target creature can't be blocked this turn. | Viktor Titov
Guardian of Tazeem | Creature | Sphinx | Flying
Landfall — Whenever a land enters the battlefield under your control, tap target creature an opponent controls. If that land is an Island, that creature doesn't untap during its controller's next untap step. | Zack Stella
Halimar Tidecaller | Creature | Human Wizard Ally | When Halimar Tidecaller enters the battlefield, you may return target card with awaken from your graveyard to your hand.
Land creatures you control have flying. | Magali Villeneuve
Wave-Wing Elemental | Creature | Elemental | Flying
Landfall — Whenever a land enters the battlefield under your control, Wave-Wing Elemental gets +2/+2 until end of turn. | John Severin Brassell
Windrider Patrol | Creature | Merfolk Wizard | Flying
Whenever Windrider Patrol deals combat damage to a player, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.) | Svetlin Velinov
Noyan Dar, Roil Shaper | Legendary Creature | Merfolk Ally | Whenever you cast an instant or sorcery spell, you may put three +1/+1 counters on target land you control. If you do, that land becomes a 0/0 Elemental creature with haste that's still a land. | Karl Kopinski
Skyrider Elf | Creature | Elf Warrior Ally | Flying
Converge — Skyrider Elf enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it. | Dan Scott
Cryptic Cruiser | Creature | Eldrazi Processor | Devoid (This card has no color.)
{2}{U}, Put a card an opponent owns from exile into that player's graveyard: Tap target creature. | Svetlin Velinov
Fathom Feeder | Creature | Eldrazi Drone | Devoid (This card has no color.)
Deathtouch
Ingest (Whenever this creature deals combat damage to a player, that player exiles the top card of their library.)
{3}{U}{B}: Draw a card. Each opponent exiles the top card of their library. | Clint Cearley