Mystical Tutor

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

Command Tower

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

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Squee, the Immortal

You may cast Squee, the Immortal from your graveyard or from exile.

Ryan Sinclair

Whenever Ryan attacks, exile cards from the top of your library until you exile a nonland card. You may cast the exiled card without paying its mana cost if it's a spell with mana value less than or equal to Ryan's power. Put the exiled cards not cast this way on the bottom of your library in a random order.
Doctor's companion (You can have two commanders if the other is the Doctor.)

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.

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

Island

Wooded Foothills

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

The Third Doctor

Trample
The Third Doctor gets +1/+1 for each noncreature token you control.
When The Third Doctor enters, create your choice of a Clue token, a Food token, or a Treasure token.

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.

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.)

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: 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.

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.

Sarah Jane Smith

Whenever you cast a historic spell, investigate. This ability triggers only once each turn. (Artifacts, legendaries, and Sagas are historic. To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Doctor's companion (You can have two commanders if the other is the Doctor.)

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Gemstone Caverns

If Gemstone Caverns is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Eternal Scourge

You may cast Eternal Scourge from exile.
When Eternal Scourge becomes the target of a spell or ability an opponent controls, exile Eternal Scourge.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Tidechannel Pathway

Barkchannel Pathway

Barkchannel Pathway // Tidechannel Pathway

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Timbercrown Pathway

Cragcrown Pathway

Cragcrown Pathway // Timbercrown Pathway

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Misthollow Griffin

Flying
You may cast Misthollow Griffin from exile.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

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}.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Talisman of Curiosity

{T}: Add {C}.
{T}: Add {G} or {U}. Talisman of Curiosity deals 1 damage to you.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Food Chain

Exile a creature you control: Add X mana of any one color, where X is 1 plus the exiled creature's mana value. Spend this mana only to cast creature spells.

Sol Ring

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.

Ragavan, Nimble Pilferer

Whenever Ragavan, Nimble Pilferer deals combat damage to a player, create a Treasure token and exile the top card of that player's library. Until end of turn, you may cast that card.
Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Dreamroot Cascade

Dreamroot Cascade enters tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

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.

Fierce Guardianship

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

Misty Rainforest

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

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

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.

Exotic Orchard

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

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Arcane Signet

Talisman of Impulse

{T}: Add {C}.
{T}: Add {R} or {G}. Talisman of Impulse deals 1 damage to you.

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Forest

Mountain

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.

Grove of the Burnwillows

{T}: Add {C}.
{T}: Add {R} or {G}. Each opponent gains 1 life.

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.