Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Have

Mana Vault

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault.
At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Sword of War and Peace

Equipped creature gets +2/+2 and has protection from red and from white.
Whenever equipped creature deals combat damage to a player, Sword of War and Peace deals damage to that player equal to the number of cards in their hand and you gain 1 life for each card in your hand.
Equip {2}

Meteor Golem

When Meteor Golem enters the battlefield, destroy target nonland permanent an opponent controls.

Grand Abolisher

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Time Warp

Target player takes an extra turn after this one.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Thought Monitor

Affinity for artifacts
Flying
When Thought Monitor enters the battlefield, draw two cards.

Unquestioned Authority

Enchant creature
When Unquestioned Authority enters the battlefield, draw a card.
Enchanted creature has protection from creatures.

Thassa's Oracle

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Steelshaper's Gift

Search your library for an Equipment card, reveal that card, put it into your hand, then shuffle.

Security Bypass

Enchant creature
As long as enchanted creature is attacking alone, it can't be blocked.
Enchanted creature has "Whenever this creature deals combat damage to a player, it connives." (Its controller draws a card, then discards a card. If they discarded a nonland card, they put a +1/+1 counter on this creature.)

Pilgrim's Eye

Flying
When Pilgrim's Eye enters the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Mnemonic Wall

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

Ichor Wellspring

When Ichor Wellspring enters the battlefield or is put into a graveyard from the battlefield, draw a card.

Chrome Mox

Imprint — When Chrome Mox enters the battlefield, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Inspiring Overseer

Flying
When Inspiring Overseer enters the battlefield, you gain 1 life and draw a card.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Meteorite

When Meteorite enters the battlefield, it deals 2 damage to any target.
{T}: Add one mana of any color.

Archaeomancer's Map

When Archaeomancer's Map enters the battlefield, search your library for up to two basic Plains cards, reveal them, put them into your hand, then shuffle.
Whenever a land enters the battlefield under an opponent's control, if that player controls more lands than you, you may put a land card from your hand onto the battlefield.

Getting

Temporal Manipulation

Counterspell

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Aqueous Form

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.)

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Island

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

Sun Titan

Vigilance
Whenever Sun Titan enters the battlefield or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Inquisitor Exarch

When Inquisitor Exarch enters the battlefield, choose one —
• You gain 2 life.
• Target opponent loses 2 life.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Remove

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Urza, Lord High Artificer

When Urza, Lord High Artificer enters the battlefield, create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Plains

Sludge Monster

Whenever Sludge Monster enters the battlefield or attacks, put a slime counter on up to one other target creature.
Non-Horror creatures with slime counters on them lose all abilities and have base power and toughness 2/2.

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Sword of Hearth and Home

Equipped creature gets +2/+2 and has protection from green and from white.
Whenever equipped creature deals combat damage to a player, exile up to one target creature you own, then search your library for a basic land card. Put both cards onto the battlefield under your control, then shuffle.
Equip {2}

Runaway Boulder

Flash
When Runaway Boulder enters the battlefield, it deals 6 damage to target creature an opponent controls.
Cycling {2} ({2}, Discard this card: Draw a card.)

Stoneforge Mystic

When Stoneforge Mystic enters the battlefield, you may search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
{1}{W}, {T}: You may put an Equipment card from your hand onto the battlefield.

Sol Ring

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Archaeomancer

When Archaeomancer enters the battlefield, return target instant or sorcery card from your graveyard to your hand.

Adric, Mathematical Genius

{2}{U}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
Ultimate Sacrifice — {1}{U}, Sacrifice Adric: Counter target activated or triggered ability.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Brago, King Eternal

Flying
Whenever Brago, King Eternal deals combat damage to a player, exile any number of target nonland permanents you control, then return those cards to the battlefield under their owner's control.

Glacial Fortress

Glacial Fortress enters the battlefield tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Gilded Lotus

Alchemist's Vial

When Alchemist's Vial enters the battlefield, draw a card.
{1}, {T}, Sacrifice Alchemist's Vial: Target creature can't attack or block this turn.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Port Town

As Port Town enters the battlefield, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters the battlefield tapped.
{T}: Add {W} or {U}.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Seat of the Synod

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter the battlefield as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Circuit Mender

When Circuit Mender enters the battlefield, you gain 2 life.
When Circuit Mender leaves the battlefield, draw a card.

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.

Command Tower

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

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Traveler's Cloak

Enchant creature
As Traveler's Cloak enters the battlefield, choose a land type.
When Traveler's Cloak enters the battlefield, draw a card.
Enchanted creature has landwalk of the chosen type. (It can't be blocked as long as defending player controls a land of that type.)

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Grim Monolith

Grim Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap Grim Monolith.

Panharmonicon

If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Spellseeker

When Spellseeker enters the battlefield, you may search your library for an instant or sorcery card with mana value 2 or less, reveal it, put it into your hand, then shuffle.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Cloudblazer

Flying
When Cloudblazer enters the battlefield, you gain 2 life and draw two cards.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Kor Cartographer

When Kor Cartographer enters the battlefield, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Spirit Mantle

Enchant creature
Enchanted creature gets +1/+1 and has protection from creatures.

Pentarch Ward

Enchant creature
As Pentarch Ward enters the battlefield, choose a color.
When Pentarch Ward enters the battlefield, draw a card.
Enchanted creature has protection from the chosen color. This effect doesn't remove Pentarch Ward.

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Wall of Omens

Defender
When Wall of Omens enters the battlefield, draw a card.

Stonehewer Giant

Vigilance
{1}{W}, {T}: Search your library for an Equipment card, put it onto the battlefield, attach it to a creature you control, then shuffle.