Dragonskull Summit

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Midnight Crusader Shuttle

Midnight Entity — Whenever Midnight Crusader Shuttle attacks, defending player faces a villainous choice — That player sacrifices a creature, or you gain control of a creature of your choice that player controls until end of turn. If you gain control of a creature this way, tap it, and it's attacking that player.
Crew 2

Talisman of Indulgence

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

Murder

Contagion Clasp

When Contagion Clasp enters the battlefield, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Djeru's Resolve

Untap target creature. Prevent all damage that would be dealt to it this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Plains

Grateful Apparition

Flying
Whenever Grateful Apparition deals combat damage to a player or planeswalker, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Blackcleave Cliffs

Blackcleave Cliffs enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {B} or {R}.

Restless Bivouac

Restless Bivouac enters the battlefield tapped.
{T}: Add {R} or {W}.
{1}{R}{W}: Restless Bivouac becomes a 2/2 red and white Ox creature until end of turn. It's still a land.
Whenever Restless Bivouac attacks, put a +1/+1 counter on target creature you control.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Shineshadow Snarl

As Shineshadow Snarl enters the battlefield, you may reveal a Plains or Swamp card from your hand. If you don't, Shineshadow Snarl enters the battlefield tapped.
{T}: Add {W} or {B}.

Rebuff the Wicked

Counter target spell that targets a permanent you control.

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

Canyon Slough

({T}: Add {B} or {R}.)
Canyon Slough enters the battlefield tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swords to Plowshares

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

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Clifftop Retreat

Clifftop Retreat enters the battlefield tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Call for Aid

Gain control of all creatures target opponent controls until end of turn. Untap those creatures. They gain haste until end of turn. You can't attack that player this turn. You can't sacrifice those creatures this turn.

Dash Hopes

When you cast this spell, any player may pay 5 life. If a player does, counter Dash Hopes.
Counter target spell.

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Lapse of Certainty

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Tevesh Szat, Doom of Fools

+2: Create two 0/1 black Thrull creature tokens.
+1: You may sacrifice another creature or planeswalker. If you do, draw two cards, then draw another card if the sacrificed permanent was a commander.
−10: Gain control of all commanders. Put all commanders from the command zone onto the battlefield under your control.
Tevesh Szat, Doom of Fools can be your commander.
Partner

Vat Emergence

Put target creature card from a graveyard onto the battlefield under your control. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Burst of Energy

Burnout

Counter target instant spell if it's blue.
Draw a card at the beginning of the next turn's upkeep.

Boros Signet

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Arcane Signet

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

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Staff of Compleation

{T}, Pay 1 life: Destroy target permanent you own.
{T}, Pay 2 life: Add one mana of any color.
{T}, Pay 3 life: Proliferate.
{T}, Pay 4 life: Draw a card.
{5}: Untap Staff of Compleation.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Mountain

Withering Boon

As an additional cost to cast this spell, pay 3 life.
Counter target creature spell.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Drown in Ichor

Target creature gets -4/-4 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Cacophony Scamp

Whenever Cacophony Scamp deals combat damage to a player, you may sacrifice it. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
When Cacophony Scamp dies, it deals damage equal to its power to any target.

Alarum

Untap target nonattacking creature. It gets +1/+3 until end of turn.

Tear

Destroy target enchantment.
Fuse (You may cast one or both halves of this card from your hand.)

Wear

Destroy target artifact.
Fuse (You may cast one or both halves of this card from your hand.)

Wear // Tear

Mana Tithe

Counter target spell unless its controller pays {1}.

Restless Fortress

Restless Fortress enters the battlefield tapped.
{T}: Add {W} or {B}.
{2}{W}{B}: Restless Fortress becomes a 1/4 white and black Nightmare creature until end of turn. It's still a land.
Whenever Restless Fortress attacks, defending player loses 2 life and you gain 2 life.

Twinflame

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.

Nomad Outpost

Nomad Outpost enters the battlefield tapped.
{T}: Add {R}, {W}, or {B}.

Go for the Throat

Illumination

Counter target artifact or enchantment spell. Its controller gains life equal to its mana value.

Reverberate

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

Inspirit

Untap target creature. It gets +2/+4 until end of turn.

Dawn Charm

Choose one —
• Prevent all combat damage that would be dealt this turn.
• Regenerate target creature.
• Counter target spell that targets you.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Swamp

Grim Affliction

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Scheming Aspirant

Whenever you proliferate, each opponent loses 2 life and you gain 2 life.

Herald of Leshrac

Flying
Cumulative upkeep—Gain control of a land you don't control. (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.)
Herald of Leshrac gets +1/+1 for each land you control but don't own.
When Herald of Leshrac leaves the battlefield, each player gains control of each land they own that you control.

Hellkite Tyrant

Flying, trample
Whenever Hellkite Tyrant deals combat damage to a player, gain control of all artifacts that player controls.
At the beginning of your upkeep, if you control twenty or more artifacts, you win the game.

Deathgrip

Sword of Truth and Justice

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Equip {2}

Battlemage's Bracers

Equipped creature has haste.
Whenever an ability of equipped creature is activated, if it isn't a mana ability, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
Equip {2}

Dualcaster Mage

Flash
When Dualcaster Mage enters the battlefield, copy target instant or sorcery spell. You may choose new targets for the copy.

Artifact Blast

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Talisman of Conviction

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

Bruse Tarl, Boorish Herder

Whenever Bruse Tarl, Boorish Herder enters the battlefield or attacks, target creature you control gains double strike and lifelink until end of turn.
Partner (You can have two commanders if both have partner.)

Molten Influence

Counter target instant or sorcery spell unless its controller has Molten Influence deal 4 damage to them.

Chef's Kiss

Gain control of target spell that targets only a single permanent or player. Copy it, then reselect the targets at random for the spell and the copy. The new targets can't be you or a permanent you control.

Mage's Attendant

When Mage's Attendant enters the battlefield, create a 1/1 blue Wizard creature token with "{1}, Sacrifice this creature: Counter target noncreature spell unless its controller pays {1}."

Act of Heroism

Untap target creature. It gets +2/+2 until end of turn and can block an additional creature 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.

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

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.

Insurrection

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Blightbelly Rat

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Blightbelly Rat dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Concealed Courtyard

Concealed Courtyard enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {W} or {B}.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Sol Ring

Generous Gift

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

Unlicensed Disintegration

Destroy target creature. If you control an artifact, Unlicensed Disintegration deals 3 damage to that creature's controller.