Durnan of the Yawning Portal

Whenever Durnan attacks, look at the top four cards of your library. You may exile a creature card from among them. Put the rest on the bottom of your library in any order. For as long as that card remains exiled, you may cast it. That spell has undaunted. (It costs {1} less to cast for each opponent.)
Choose a Background (You can have a Background as a second commander.)

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Grumgully, the Generous

Each other non-Human creature you control enters the battlefield with an additional +1/+1 counter on it.

Xenagos, the Reveler

+1: Add X mana in any combination of {R} and/or {G}, where X is the number of creatures you control.
0: Create a 2/2 red and green Satyr creature token with haste.
−6: Exile the top seven cards of your library. You may put any number of creature and/or land cards from among them onto the battlefield.

Chaos Wand

{4}, {T}: Target opponent exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then put the exiled cards that weren't cast this way on the bottom of that library in a random order.

Mossfire Valley

Dream Pillager

Flying
Whenever Dream Pillager deals combat damage to a player, exile that many cards from the top of your library. Until end of turn, you may cast spells from among those exiled cards.

Izzet Chemister

Haste
{R}, {T}: Exile target instant or sorcery card from your graveyard.
{1}{R}, {T}, Sacrifice Izzet Chemister: Cast any number of cards exiled with Izzet Chemister without paying their mana costs.

Explore

You may play an additional land this turn.
Draw a card.

Demon Bolt

Demon Bolt deals 4 damage to target creature or planeswalker.
Foretell {R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Bloodbraid Elf

Haste
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Arcane Signet

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

End-Raze Forerunners

Vigilance, trample, haste
When End-Raze Forerunners enters the battlefield, other creatures you control get +2/+2 and gain vigilance and trample until end of turn.

Forest

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Wild Ricochet

You may choose new targets for target instant or sorcery spell. Then copy that spell. You may choose new targets for the copy.

Aurora Phoenix

Flying
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Whenever you cast a spell with cascade, return Aurora Phoenix from your graveyard to your hand.

Nalfeshnee

Flying
Whenever you cast a spell from exile, copy it. You may choose new targets for the copy. If it's a permanent spell, the copy gains haste and "At the beginning of the end step, sacrifice this permanent." (A copy of a permanent spell becomes a token.)

Green Slime

Flash
When Green Slime enters the battlefield, counter target activated or triggered ability from an artifact or enchantment source. If a permanent's ability is countered this way, destroy that permanent.
Foretell {G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Passionate Archaeologist

Commander creatures you own have "Whenever you cast a spell from exile, this creature deals damage equal to that spell's mana value to target opponent."

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter the battlefield with your choice of a +1/+1 counter or haste.)

Gruul Turf

Gruul Turf enters the battlefield tapped.
When Gruul Turf enters the battlefield, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Mosswort Bridge

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Mosswort Bridge enters the battlefield tapped.
{T}: Add {G}.
{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Laelia, the Blade Reforged

Haste
Whenever Laelia, the Blade Reforged attacks, exile the top card of your library. You may play that card this turn.
Whenever one or more cards are put into exile from your library and/or your graveyard, put a +1/+1 counter on Laelia.

Sarevok's Tome

When Sarevok's Tome enters the battlefield, you take the initiative.
{T}: Add {C}. If you have the initiative, add {C}{C} instead.
{3}, {T}: Exile cards from the top of your library until you exile a nonland card. You may cast that card without paying its mana cost. Activate only if you've completed a dungeon.

Sandwurm Convergence

Creatures with flying can't attack you or planeswalkers you control.
At the beginning of your end step, create a 5/5 green Wurm creature token.

Tectonic Giant

Whenever Tectonic Giant attacks or becomes the target of a spell an opponent controls, choose one —
• Tectonic Giant deals 3 damage to each opponent.
• Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.

Heart's Desire

Create a 1/1 white Human creature token. (Then exile this card. You may cast the creature later from exile.)

Lovestruck Beast

Lovestruck Beast can't attack unless you control a 1/1 creature.

Lovestruck Beast // Heart's Desire

Castle Embereth

Castle Embereth enters the battlefield tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

Vivien, Champion of the Wilds

You may cast creature spells as though they had flash.
+1: Until your next turn, up to one target creature gains vigilance and reach.
−2: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may look at that card and you may cast it if it's a creature spell.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Delayed Blast Fireball

Delayed Blast Fireball deals 2 damage to each opponent and each creature they control. If this spell was cast from exile, it deals 5 damage to each opponent and each creature they control instead.
Foretell {4}{R}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Spinerock Knoll

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Spinerock Knoll enters the battlefield tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Cultivate

Temple of Abandon

Temple of Abandon enters the battlefield tapped.
When Temple of Abandon enters the battlefield, scry 1.
{T}: Add {R} or {G}.

Journey to the Lost City

At the beginning of your upkeep, exile the top four cards of your library, then roll a d20.
1—9 | You may put a land card from among those cards onto the battlefield.
10—19 | Create a 2/2 green Wolf creature token, then put a +1/+1 counter on it for each creature card among those cards.
20 | Put all permanent cards exiled with Journey to the Lost City onto the battlefield, then sacrifice it.

Command Tower

Warstorm Surge

Whenever a creature enters the battlefield under your control, it deals damage equal to its power to any target.

Battle Display

Destroy target artifact. (Then exile this card. You may cast the creature later from exile.)

Embereth Shieldbreaker

Embereth Shieldbreaker // Battle Display

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Beast Within

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

Retrieve Prey

Exile target creature card from your graveyard. Until the end of your next turn, you may cast that card. (Then exile this card. You may cast the creature later from exile.)

Tlincalli Hunter

Trample
Once each turn, you may pay {0} rather than pay the mana cost for a creature spell you cast from exile.

Tlincalli Hunter // Retrieve Prey

Arasta of the Endless Web

Reach
Whenever an opponent casts an instant or sorcery spell, create a 1/2 green Spider creature token with reach.

Venture Forth

Exile cards from the top of your library until you exile a land card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. Exile Venture Forth with three time counters on it.
Suspend 3—{1}{G}

Outpost Siege

As Outpost Siege enters the battlefield, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card.
• Dragons — Whenever a creature you control leaves the battlefield, Outpost Siege deals 1 damage to any target.

Urabrask, Heretic Praetor

Haste
At the beginning of your upkeep, exile the top card of your library. You may play it this turn.
At the beginning of each opponent's upkeep, the next time they would draw a card this turn, instead they exile the top card of their library. They may play it this turn.

Escape to the Wilds

Exile the top five cards of your library. You may play cards exiled this way until the end of your next turn.
You may play an additional land this turn.

Blighted Woodland

{T}: Add {C}.
{3}{G}, {T}, Sacrifice Blighted Woodland: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Natural Reclamation

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Destroy target artifact or enchantment.

Search for Tomorrow

Search your library for a basic land card, put it onto the battlefield, then shuffle.
Suspend 2—{G} (Rather than cast this card from your hand, you may pay {G} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Raging Ravine

Raging Ravine enters the battlefield tapped.
{T}: Add {R} or {G}.
{2}{R}{G}: Until end of turn, Raging Ravine becomes a 3/3 red and green Elemental creature with "Whenever this creature attacks, put a +1/+1 counter on it." It's still a land.

Greater Gargadon

Suspend 10—{R}
Sacrifice an artifact, creature, or land: Remove a time counter from Greater Gargadon. Activate only if Greater Gargadon is suspended.

Wild-Magic Sorcerer

The first spell you cast from exile each turn has cascade. (When you cast your first spell from exile, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Ignite the Future

Exile the top three cards of your library. Until the end of your next turn, you may play those cards. If this spell was cast from a graveyard, you may play cards this way without paying their mana costs.
Flashback {7}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Urabrask the Hidden

Creatures you control have haste.
Creatures your opponents control enter the battlefield tapped.

Dire Fleet Daredevil

First strike
When Dire Fleet Daredevil enters the battlefield, exile target instant or sorcery card from an opponent's graveyard. You may cast it this turn, and mana of any type can be spent to cast that spell. If that spell would be put into a graveyard, exile it instead.

Sweet-Gum Recluse

Flash
Cascade
Reach
When Sweet-Gum Recluse enters the battlefield, put three +1/+1 counters on each of any number of target creatures that entered the battlefield this turn.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters the battlefield tapped.

Game Trail

As Game Trail enters the battlefield, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters the battlefield tapped.
{T}: Add {R} or {G}.

Sol Ring

Stomp

Damage can't be prevented this turn. Stomp deals 2 damage to any target.

Bonecrusher Giant

Whenever Bonecrusher Giant becomes the target of a spell, Bonecrusher Giant deals 2 damage to that spell's controller.

Bonecrusher Giant // Stomp

Battle Mammoth

Trample
Whenever a permanent you control becomes the target of a spell or ability an opponent controls, you may draw a card.
Foretell {2}{G}{G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Primeval Bounty

Whenever you cast a creature spell, create a 3/3 green Beast creature token.
Whenever you cast a noncreature spell, put three +1/+1 counters on target creature you control.
Landfall — Whenever a land enters the battlefield under your control, you gain 3 life.

Stolen Strategy

At the beginning of your upkeep, exile the top card of each opponent's library. Until end of turn, you may cast spells from among those exiled cards, and you may spend mana as though it were mana of any color to cast those spells.

Mountain

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Volcanic Torrent

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Volcanic Torrent deals X damage to each creature and planeswalker your opponents control, where X is the number of spells you've cast this turn.

Terramorph

Search your library for a basic land card, put it onto the battlefield, then shuffle.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Fertile Footsteps

Search your library for a basic land card, put it onto the battlefield, then shuffle. (Then exile this card. You may cast the creature later from exile.)

Beanstalk Giant

Beanstalk Giant's power and toughness are each equal to the number of lands you control.

Beanstalk Giant // Fertile Footsteps

Etali, Primal Storm

Whenever Etali, Primal Storm attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Faldorn, Dread Wolf Herald

Whenever you cast a spell from exile or a land enters the battlefield under your control from exile, create a 2/2 green Wolf creature token.
{1}, {T}, Discard a card: Exile the top card of your library. You may play it this turn.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters the battlefield tapped unless you control two or more basic lands.

Hornet Queen

Flying, deathtouch
When Hornet Queen enters the battlefield, create four 1/1 green Insect creature tokens with flying and deathtouch.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Ezuri's Predation

For each creature your opponents control, create a 4/4 green Phyrexian Beast creature token. Each of those tokens fights a different one of those creatures.