Island

Inkwell Leviathan

Trample
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Shroud (This creature can't be the target of spells or abilities.)

Aether Adept

When Aether Adept enters, return target creature to its owner's hand.

Shortcut Seeker

Whenever Shortcut Seeker deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Visions of Duplicity

Exchange control of two target creatures you don't control.
Flashback {8}{U}{U}. This spell costs {X} less to cast this way, where X is the greatest mana value of a commander you own on the battlefield or in the command zone. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Negate

Augury Owl

Flying
When Augury Owl enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Tempted by the Oriq

For each opponent, gain control of up to one target creature or planeswalker that player controls with mana value 3 or less.

Unsummon

Return target creature to its owner's hand.

Secrets of the Key

Investigate. If this spell was cast from a graveyard, investigate twice instead. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Flashback {3}{U}

Mind Control

Enchant creature
You control enchanted creature.

Neurok Commando

Shroud (This creature can't be the target of spells or abilities.)
Whenever Neurok Commando deals combat damage to a player, you may draw a card.

Power of Persuasion

Choose target creature an opponent controls, then roll a d20.
1—9 | Return it to its owner's hand.
10—19 | Its owner puts it on their choice of the top or bottom of their library.
20 | Gain control of it until the end of your next turn.

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Sealock Monster

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.

Vapor Snag

Return target creature to its owner's hand. Its controller loses 1 life.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Drownyard Amalgam

When Drownyard Amalgam enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)
{2}{U}: Drownyard Amalgam can't be blocked this turn.

Harbor Serpent

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Harbor Serpent can't attack unless there are five or more Islands on the battlefield.

Unblinking Observer

{T}: Add {U}. Spend this mana only to pay a disturb cost or cast an instant or sorcery spell.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Cancel

Curse of the Bloody Tome

Enchant player
At the beginning of enchanted player's upkeep, that player mills two cards.

Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Blighted Agent can't be blocked.

Merfolk Spy

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Merfolk Spy deals combat damage to a player, that player reveals a card at random from their hand.

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Ice Cage

Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated.
When enchanted creature becomes the target of a spell or ability, destroy Ice Cage.

Tome Scour

Ominous Roost

When Ominous Roost enters and whenever you cast a spell from your graveyard, create a 1/1 blue Bird creature token with flying and "This creature can block only creatures with flying."

Levitation

Revenge of the Drowned

Target creature's owner puts it on their choice of the top or bottom of their library. You create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Millstone

Keening Stone

{5}, {T}: Target player mills X cards, where X is the number of cards in that player's graveyard.

Lier, Disciple of the Drowned

Spells can't be countered.
Each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost.

Hook-Haunt Drifter

Flying
If Hook-Haunt Drifter would be put into a graveyard from anywhere, exile it instead.

Baithook Angler

Disturb {1}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Baithook Angler // Hook-Haunt Drifter

Otherworldly Gaze

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Divide by Zero

Return target spell or permanent with mana value 1 or greater to its owner's hand.
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

Vivisection

As an additional cost to cast this spell, sacrifice a creature.
Draw three cards.

Jace Beleren

+2: Each player draws a card.
−1: Target player draws a card.
−10: Target player mills twenty cards.

Firmament Sage

If it's neither day nor night, it becomes day as Firmament Sage enters.
Whenever day becomes night or night becomes day, draw a card.

Skaab Wrangler

Tap three untapped creatures you control: Tap target creature.

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.