Theros

Annul | Instant | | Counter target artifact or enchantment spell. | Christine Choi

Aqueous Form | Enchantment | Aura | Enchant creature Enchanted creature can't be blocked. Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Slawomir Maniak

Artisan of Forms | Creature | Human Wizard | Heroic — Whenever you cast a spell that targets Artisan of Forms, you may have Artisan of Forms become a copy of target creature, except it has this ability. | Min Yum

Benthic Giant | Creature | Giant | Hexproof (This creature can't be the target of spells or abilities your opponents control.) | Jaime Jones

Bident of Thassa | Legendary Enchantment Artifact | | Whenever a creature you control deals combat damage to a player, you may draw a card. {1}{U}, {T}: Creatures your opponents control attack this turn if able. | Yeong-Hao Han

Breaching Hippocamp | Creature | Horse Fish | Flash (You may cast this spell any time you could cast an instant.) When Breaching Hippocamp enters the battlefield, untap another target creature you control. | Christopher Burdett

Coastline Chimera | Creature | Chimera | Flying {1}{W}: Coastline Chimera can block an additional creature this turn. | Dan Scott

Crackling Triton | Creature | Merfolk Wizard | {2}{R}, Sacrifice Crackling Triton: It deals 2 damage to any target. | Greg Staples

Curse of the Swine | Sorcery | | Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token. | James Ryman

Dissolve | Instant | | Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Wesley Burt

Fate Foretold | Enchantment | Aura | Enchant creature When Fate Foretold enters the battlefield, draw a card. When enchanted creature dies, its controller draws a card. | Dan Scott

Gainsay | Instant | | Counter target blue spell. | Clint Cearley

Griptide | Instant | | Put target creature on top of its owner's library. | Adam Paquette

Horizon Scholar | Creature | Sphinx | Flying When Horizon Scholar enters the battlefield, 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.) | Karl Kopinski

Lost in a Labyrinth | Instant | | Target creature gets -3/-0 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Winona Nelson

Master of Waves | Creature | Merfolk Wizard | Protection from red Elemental creatures you control get +1/+1. When Master of Waves enters the battlefield, create a number of 1/0 blue Elemental creature tokens equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.) | Karl Kopinski

Meletis Charlatan | Creature | Human Wizard | {2}{U}, {T}: The controller of target instant or sorcery spell copies it. That player may choose new targets for the copy. | Jason A. Engle

Mnemonic Wall | Creature | Wall | Defender When Mnemonic Wall enters the battlefield, you may return target instant or sorcery card from your graveyard to your hand. | Trevor Claxton

Nimbus Naiad | Enchantment Creature | Nymph | Bestow {4}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.) Flying Enchanted creature gets +2/+2 and has flying. | David Palumbo

Omenspeaker | Creature | Human Wizard | When Omenspeaker enters the battlefield, 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.) | Dallas Williams

Ordeal of Thassa | Enchantment | Aura | Enchant creature Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice Ordeal of Thassa. When you sacrifice Ordeal of Thassa, draw two cards. | Howard Lyon

Prescient Chimera | Creature | Chimera | Flying Whenever you cast an instant or sorcery spell, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Daarken

Prognostic Sphinx | Creature | Sphinx | Flying Discard a card: Prognostic Sphinx gains hexproof until end of turn. Tap it. Whenever Prognostic Sphinx attacks, scry 3. | Steve Prescott

Sea God's Revenge | Sorcery | | Return up to three target creatures your opponents control to their owners' hands. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Eric Velhagen

Sealock Monster | Creature | Octopus | Sealock Monster can't attack unless defending player controls an Island. {5}{U}{U}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.) When Sealock Monster becomes monstrous, target land becomes an Island in addition to its other types. | Adam Paquette

Shipbreaker Kraken | Creature | Kraken | {6}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.) When Shipbreaker Kraken becomes monstrous, tap up to four target creatures. Those creatures don't untap during their controllers' untap steps for as long as you control Shipbreaker Kraken. | Jack Wang

Stymied Hopes | Instant | | Counter target spell unless its controller pays {1}. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Peter Mohrbacher

Swan Song | Instant | | Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying. | Peter Mohrbacher

Thassa, God of the Sea | Legendary Enchantment Creature | God | Indestructible As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.) At the beginning of your upkeep, scry 1. {1}{U}: Target creature you control can't be blocked this turn. | Jason Chan

Thassa's Bounty | Sorcery | | Draw three cards. Target player mills three cards. | Ryan Yee

Thassa's Emissary | Enchantment Creature | Crab | Bestow {5}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.) Whenever Thassa's Emissary or enchanted creature deals combat damage to a player, draw a card. Enchanted creature gets +3/+3. | Sam Burley

Triton Fortune Hunter | Creature | Merfolk Soldier | Heroic — Whenever you cast a spell that targets Triton Fortune Hunter, draw a card. | Clint Cearley

Triton Shorethief | Creature | Merfolk Rogue | | Howard Lyon

Triton Tactics | Instant | | Up to two target creatures each get +0/+3 until end of turn. Untap those creatures. At this turn's next end of combat, tap each creature that was blocked by one of those creatures this turn and it doesn't untap during its controller's next untap step. | Jack Wang

Vaporkin | Creature | Elemental | Flying Vaporkin can block only creatures with flying. | Seb McKinnon

Voyage's End | Instant | | Return target creature to its owner's hand. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) | Chris Rahn

Wavecrash Triton | Creature | Merfolk Wizard | Heroic — Whenever you cast a spell that targets Wavecrash Triton, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step. | Ryan Barger

Returned Phalanx | Creature | Zombie Soldier | Defender {1}{U}: Returned Phalanx can attack this turn as though it didn't have defender. | Seb McKinnon

Agent of Horizons | Creature | Human Rogue | {2}{U}: Agent of Horizons can't be blocked this turn. | Clint Cearley

Battlewise Hoplite | Creature | Human Soldier | Heroic — Whenever you cast a spell that targets Battlewise Hoplite, put a +1/+1 counter on Battlewise Hoplite, then scry 1. (To scry 1, look at the top card of your library, then you may put that card on the bottom of your library.) | Willian Murai

Daxos of Meletis | Legendary Creature | Human Soldier | Daxos of Meletis can't be blocked by creatures with power 3 or greater. Whenever Daxos of Meletis deals combat damage to a player, exile the top card of that player's library. You gain life equal to that card's mana value. Until end of turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell. | Karla Ortiz

Medomai the Ageless | Legendary Creature | Sphinx | Flying Whenever Medomai the Ageless deals combat damage to a player, take an extra turn after this one. Medomai the Ageless can't attack during extra turns. | David Palumbo

Ashiok, Nightmare Weaver | Legendary Planeswalker | Ashiok | +2: Exile the top three cards of target opponent's library. −X: Put a creature card with mana value X exiled with Ashiok, Nightmare Weaver onto the battlefield under your control. That creature is a Nightmare in addition to its other types. −10: Exile all cards from all opponents' hands and graveyards. | Karla Ortiz

Psychic Intrusion | Sorcery | | Target opponent reveals their hand. You choose a nonland card from that player's graveyard or hand and exile it. You may cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell. | Jaime Jones

Shipwreck Singer | Creature | Siren | Flying {1}{U}: Target creature an opponent controls attacks this turn if able. {1}{B}, {T}: Attacking creatures get -1/-1 until end of turn. | Daarken

Spellheart Chimera | Creature | Chimera | Flying, trample Spellheart Chimera's power is equal to the number of instant and sorcery cards in your graveyard. | Svetlin Velinov

Steam Augury | Instant | | Reveal the top five cards of your library and separate them into two piles. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard. | Dave Kendall

Horizon Chimera | Creature | Chimera | Flash Flying, trample Whenever you draw a card, you gain 1 life. | Sam Burley

Prophet of Kruphix | Creature | Human Wizard | Untap all creatures and lands you control during each other player's untap step. You may cast creature spells as though they had flash. | Winona Nelson

Temple of Deceit | Land | | Temple of Deceit enters the battlefield tapped. When Temple of Deceit enters the battlefield, scry 1. {T}: Add {U} or {B}. | Raymond Swanland

Temple of Mystery | Land | | Temple of Mystery enters the battlefield tapped. When Temple of Mystery enters the battlefield, scry 1. {T}: Add {G} or {U}. | Noah Bradley

Island | Basic Land | Island | ({T}: Add {U}.) | Rob Alexander

Island | Basic Land | Island | ({T}: Add {U}.) | Steven Belledin

Island | Basic Land | Island | ({T}: Add {U}.) | Adam Paquette

Island | Basic Land | Island | ({T}: Add {U}.) | Raoul Vitale