Natural Connection

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Mindsplice Apparatus

Flash
At the beginning of your upkeep, put an oil counter on Mindsplice Apparatus.
Instant and sorcery spells you cast cost {1} less to cast for each oil counter on Mindsplice Apparatus.

Nanogene Conversion

Choose target creature you control. Each other creature becomes a copy of that creature until end of turn, except it isn't legendary.

Helm of Awakening

Mutational Advantage

Permanents you control with counters on them gain hexproof and indestructible until end of turn. Prevent all damage that would be dealt to those permanents this turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Taigam's Scheming

Surveil 5. (Look at the top five cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Contingency Plan

Tanglespan Bridgeworks

As Tanglespan Bridgeworks enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {G}.

Bridgeworks Battle

Target creature you control gets +2/+2 until end of turn. It fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)

Bridgeworks Battle // Tanglespan Bridgeworks

Simic Growth Chamber

Simic Growth Chamber enters tapped.
When Simic Growth Chamber enters, return a land you control to its owner's hand.
{T}: Add {G}{U}.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Frantic Search

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

Escape Tunnel

{T}, Sacrifice Escape Tunnel: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{T}, Sacrifice Escape Tunnel: Target creature with power 2 or less can't be blocked this turn.

Overflowing Basin

Jungle Basin

Jungle Basin enters tapped.
When Jungle Basin enters, sacrifice it unless you return an untapped Forest you control to its owner's hand.
{T}: Add {C}{G}.

Gale, Waterdeep Prodigy

Whenever you cast an instant or sorcery spell from your hand, you may cast up to one target card of the other type from your graveyard. If a spell cast from your graveyard this way would be put into your graveyard, exile it instead.
Choose a Background (You can have a Background as a second commander.)

Splendid Reclamation

Return all land cards from your graveyard to the battlefield tapped.

Coral Atoll

Coral Atoll enters tapped.
When Coral Atoll enters, sacrifice it unless you return an untapped Island you control to its owner's hand.
{T}: Add {C}{U}.

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

Far Wanderings

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
Threshold — If seven or more cards are in your graveyard, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Regrowth

Return target card from your graveyard to your hand.

Thought Scour

Target player mills two cards.
Draw a card.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Silver Scrutiny

You may cast Silver Scrutiny as though it had flash if X is 3 or less.
Draw X cards.

Pieces of the Puzzle

Reveal the top five cards of your library. Put up to two instant and/or sorcery cards from among them into your hand and the rest into your graveyard.

Into the Story

This spell costs {3} less to cast if an opponent has seven or more cards in their graveyard.
Draw four cards.

Arcane Melee

Instant and sorcery spells cost {2} less to cast.

Flood Plain

Flood Plain enters tapped.
{T}, Sacrifice Flood Plain: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Disrupt

Counter target instant or sorcery spell unless its controller pays {1}.
Draw a card.

Reverse the Polarity

Choose one —
• Counter all other spells.
• Switch each creature's power and toughness until end of turn.
• Creatures can't be blocked this turn.

Solidarity of Heroes

Strive — This spell costs {1}{G} more to cast for each target beyond the first.
Choose any number of target creatures. Double the number of +1/+1 counters on each of them.

Font of Magic

Instant and sorcery spells you cast cost {1} less to cast for each time you've cast a commander from the command zone this game.

Fangs of Kalonia

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on each creature that had a +1/+1 counter put on it this way.
Overload {4}{G}{G} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Command Tower

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

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Inspiring Call

Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Brokers Hideout

When Brokers Hideout enters, sacrifice it. When you do, search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Bushwhack

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Pore Over the Pages

Draw three cards, untap up to two lands, then discard a card.

Tangled Islet

({T}: Add {G} or {U}.)
Tangled Islet enters tapped.

Turnabout

Choose artifact, creature, or land. Tap all untapped permanents of the chosen type target player controls, or untap all tapped permanents of that type that player controls.

Bad River

Bad River enters tapped.
{T}, Sacrifice Bad River: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Thirst for Discovery

Draw three cards. Then discard two cards unless you discard a basic land card.

Commander's Insight

Target player draws X cards plus an additional card for each time they've cast a commander from the command zone this game.

Forest

Biogenic Upgrade

Distribute three +1/+1 counters among one, two, or three target creatures, then double the number of +1/+1 counters on each of those creatures.

Candlekeep Inspiration

Until end of turn, creatures you control have base power and toughness X/X, where X is the number of cards you own in exile and in your graveyard that are instant cards, are sorcery cards, and/or have an Adventure.

Consider

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

Unwind

Counter target noncreature spell. Untap up to three lands.

Rewind

Counter target spell. Untap up to four lands.

Master Chef

Commander creatures you own have "This creature enters with an additional +1/+1 counter on it" and "Other creatures you control enter with an additional +1/+1 counter on them."

Quicken

The next sorcery spell you cast this turn can be cast as though it had flash. (It can be cast any time you could cast an instant.)
Draw a card.

Counterspell

Case of the Ransacked Lab

Instant and sorcery spells you cast cost {1} less to cast.
To solve — You've cast four or more instant and sorcery spells this turn. (If unsolved, solve at the beginning of your end step.)
Solved — Whenever you cast an instant or sorcery spell, draw a card.

Peek

Look at target player's hand.
Draw a card.

Secrets of the Dead

Whenever you cast a spell from your graveyard, draw a card.

Teferi's Time Twist

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters as a creature, it enters with an additional +1/+1 counter on it.

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Chilling Trap

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

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Temple of Mystery

Temple of Mystery enters tapped.
When Temple of Mystery enters, scry 1.
{T}: Add {G} or {U}.

Arid Archway

Arid Archway enters tapped.
When Arid Archway enters, return a land you control to its owner's hand. If another Desert was returned this way, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}{C}.

Perplexing Test

Choose one —
• Return all creature tokens to their owners' hands.
• Return all nontoken creatures to their owners' hands.

Island

Flooded Grove

{T}: Add {C}.
{G/U}, {T}: Add {G}{G}, {G}{U}, or {U}{U}.

Golgari Grave-Troll

Golgari Grave-Troll enters with a +1/+1 counter on it for each creature card in your graveyard.
{1}, Remove a +1/+1 counter from Golgari Grave-Troll: Regenerate Golgari Grave-Troll.
Dredge 6 (If you would draw a card, you may mill six cards instead. If you do, return this card from your graveyard to your hand.)

Thirst for Meaning

Draw three cards. Then discard two cards unless you discard an enchantment card.

Slime Against Humanity

Create a 0/0 green Ooze creature token with trample. Put X +1/+1 counters on it, where X is two plus the total number of cards you own in exile and in your graveyard that are Oozes or are named Slime Against Humanity.
A deck can have any number of cards named Slime Against Humanity.