Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Counterspell

Ghostly Pilferer

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card.
Whenever an opponent casts a spell from anywhere other than their hand, draw a card.
Discard a card: Ghostly Pilferer can't be blocked this turn.

Orvar, the All-Form

Changeling
Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.
When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Ichor Synthesizer

Whenever you cast a noncreature spell, put an oil counter on Ichor Synthesizer.
As long as Ichor Synthesizer has four or more oil counters on it, it gets +2/+0 and can't be blocked.

Expendable Lackey

{1}{U}, Exile Expendable Lackey from your graveyard: Create a 1/1 blue Fish creature token with "This creature can't be blocked." Activate only as a sorcery.

Dreadful as the Storm

Target creature has base power and toughness 5/5 until end of turn. The Ring tempts you.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Chilling Trap

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

Unsubstantiate

Return target spell or creature to its owner's hand.

Borne Upon a Wind

You may cast spells this turn as though they had flash.
Draw a card.

Meldweb Curator

When Meldweb Curator enters the battlefield, put up to one target instant or sorcery card from your graveyard on top of your library.

Stern Scolding

Counter target creature spell with power or toughness 2 or less.

Treason of Isengard

Put up to one target instant or sorcery card from your graveyard on top of your library.
Amass Orcs 2. (To amass Orcs 2, put two +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Chain to Memory

Target creature gets -4/-0 until end of turn. Scry 2.

Desert of the Mindful

Desert of the Mindful enters the battlefield tapped.
{T}: Add {U}.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Annul

Counter target artifact or enchantment spell.

Unctus, Grand Metatect

Other blue creatures you control have "Whenever this creature becomes tapped, draw a card, then discard a card."
Other artifact creatures you control get +1/+1.
{U/P}: Until end of turn, target creature you control becomes a blue artifact in addition to its other colors and types. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)

Network Disruptor

Flying
When Network Disruptor enters the battlefield, tap target permanent.

Rookie Mistake

Until end of turn, target creature gets +0/+2 and another target creature gets -2/-0.

Soothing of Sméagol

Return target nontoken creature to its owner's hand. The Ring tempts you.

Maximize Altitude

Target creature gets +1/+1 and gains flying until end of turn.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Halo-Charged Skaab

When Halo-Charged Skaab enters the battlefield, each player mills two cards. Then you may put an instant, sorcery, or battle card from your graveyard on top of your library. (To mill two cards, a player puts the top two cards of their library into their graveyard.)

Storm of Saruman

Ward {3}
Whenever you cast your second spell each turn, copy it, except the copy isn't legendary. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Mist-Cloaked Herald

Cloudkin Seer

Flying
When Cloudkin Seer enters the battlefield, draw a card.

Memory Deluge

Look at the top X cards of your library, where X is the amount of mana spent to cast this spell. Put two of them into your hand and the rest on the bottom of your library in a random order.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Overflowing Insight

Island

Deceive the Messenger

Target creature gets -3/-0 until end of turn.
Amass Orcs 1. (Put a +1/+1 counter on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Hithlain Knots

Tap target creature. Scry 1.
Draw a card.

Manifold Key

{1}, {T}: Untap another target artifact.
{3}, {T}: Target creature can't be blocked this turn.

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Wall of Runes

Defender (This creature can't attack.)
When Wall of Runes enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Prologue to Phyresis

Each opponent gets a poison counter.
Draw a card.

Lonely Sandbar

Lonely Sandbar enters the battlefield tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

True Polymorph

Target artifact or creature becomes a copy of another target artifact or creature.

Aspirant's Ascent

Until end of turn, target creature gets +1/+3 and gains flying and toxic 1. (Players dealt combat damage by that creature also get a poison counter.)

Teferi, Temporal Pilgrim

Whenever you draw a card, put a loyalty counter on Teferi, Temporal Pilgrim.
0: Draw a card.
−2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this creature."
−12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Birthday Escape

Rangers of Ithilien

Vigilance
When Rangers of Ithilien enters the battlefield, gain control of up to one target creature with lesser power for as long as you control Rangers of Ithilien. Then the Ring tempts you.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Trawler Drake

Flying
Trawler Drake enters the battlefield with an oil counter on it.
Trawler Drake gets +1/+1 for each oil counter on it.
Whenever you cast a noncreature spell, put an oil counter on Trawler Drake.

Command Tower

Slither Blade

Majestic Metamorphosis

Until end of turn, target artifact or creature becomes a 4/4 Angel artifact creature and gains flying.
Draw a card.

Sunscorched Desert

When Sunscorched Desert enters the battlefield, it deals 1 damage to target player or planeswalker.
{T}: Add {C}.

Dive Down

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Cloud Key

As Cloud Key enters the battlefield, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Negate

Fading Hope

Return target creature to its owner's hand. If its mana value was 3 or less, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Unsummon

Return target creature to its owner's hand.

Rewind

Counter target spell. Untap up to four lands.

Zhalfirin Shapecraft

Target creature has base power and toughness 4/3 until end of turn.
Draw a card.

Preening Champion

Flying
When Preening Champion enters the battlefield, create a 1/1 blue and red Elemental creature token.

Silver Raven

Flying
When Silver Raven enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Gate to Seatower

Gate to Seatower enters the battlefield tapped.
{3}{U}, {T}: Seek a nonland card. Activate only once.
{T}: Add {U}.