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}.

Badlands

Counterspell

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Rhystic Study

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

Fierce Guardianship

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

Underground Sea

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Silence

Your opponents can't cast spells this turn.

Island

Volcanic Island

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Flusterstorm

Counter target instant or sorcery spell unless its controller pays {1}.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Arcane Signet

{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.

Hullbreacher

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Command Tower

Loyal Apprentice

Haste
Lieutenant — At the beginning of combat on your turn, if you control your commander, create a 1/1 colorless Thopter artifact creature token with flying. That token gains haste until end of turn.

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Plateau

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Ludevic, Necro-Alchemist

At the beginning of each player's end step, that player may draw a card if a player other than you lost life this turn.
Partner (You can have two commanders if both have partner.)

Chrome Mox

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

Snow-Covered Plains

Tundra

Brain Freeze

Target player mills three cards.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Fire Covenant

As an additional cost to cast this spell, pay X life.
Fire Covenant deals X damage divided as you choose among any number of target creatures.

Underworld Breach

Each nonland card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.)
At the beginning of the end step, sacrifice Underworld Breach.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Aven Mindcensor

Flash
Flying
If an opponent would search a library, that player searches the top four cards of that library instead.

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.")

Enlightened Tutor

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

Lion's Eye Diamond

Discard your hand, Sacrifice Lion's Eye Diamond: Add three mana of any one color. Activate only as an instant.

Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Dramatic Reversal

Untap all nonland permanents you control.

Scrubland

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Dockside Extortionist

When Dockside Extortionist enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mystical Tutor

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

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Angel's Grace

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
You can't lose the game this turn and your opponents can't win the game this turn. Until end of turn, damage that would reduce your life total to less than 1 reduces it to 1 instead.

Sol Ring

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Tymna the Weaver

Lifelink
At the beginning of each of your postcombat main phases, you may pay X life, where X is the number of opponents that were dealt combat damage this turn. If you do, draw X cards.
Partner (You can have two commanders if both have partner.)

Dark Confidant

At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.