Clout of the Dominus

Enchant creature
As long as enchanted creature is blue, it gets +1/+1 and has shroud. (It can't be the target of spells or abilities.)
As long as enchanted creature is red, it gets +1/+1 and has haste.

Loch Dragon

Flying
Whenever this creature enters or attacks, you may discard a card. If you do, draw a card.

Sanguine Morass

This land enters tapped.
{T}: Add {B} or {R}.

Bloodsoaked Insight

This spell costs {1} less to cast for each 1 life your opponents have lost this turn.
Target opponent exiles the top three cards of their library. Until the end of your next turn, you may play those cards. If you cast a spell this way, mana of any type can be spent to cast it.

Bloodsoaked Insight // Sanguine Morass

Crackleburr

{U/R}{U/R}, {T}, Tap two untapped red creatures you control: This creature deals 3 damage to any target.
{U/R}{U/R}, {Q}, Untap two tapped blue creatures you control: Return target creature to its owner's hand. ({Q} is the untap symbol.)

Scourge of the Nobilis

Enchant creature
As long as enchanted creature is red, it gets +1/+1 and has "{R/W}: This creature gets +1/+0 until end of turn."
As long as enchanted creature is white, it gets +1/+1 and has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)

Tattermunge Duo

Whenever you cast a red spell, this creature gets +1/+1 until end of turn.
Whenever you cast a green spell, this creature gains forestwalk until end of turn. (It can't be blocked as long as defending player controls a Forest.)

Carnage Interpreter

When this creature enters, discard your hand, then investigate four times. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
As long as you have one or fewer cards in hand, this creature gets +2/+2 and has menace.

Resonance Technician

Flying
When this creature enters, you may discard a card. If you do, investigate twice.
{T}, Tap X untapped artifacts you control: Copy target instant or sorcery spell you control with mana value X. You may choose new targets for the copy.

Mountain

Deus of Calamity

Trample
Whenever this creature deals 6 or more damage to an opponent, destroy target land that player controls.

Spitemare

Whenever this creature is dealt damage, it deals that much damage to any target.

Kulrath Knight

Flying
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Creatures your opponents control with counters on them can't attack or block.

Legion Stronghold

This land enters tapped.
{T}: Add {R} or {W}.

Legion Leadership

Until end of turn, double target creature's power and it gains first strike.

Legion Leadership // Legion Stronghold

Noggle Hedge-Mage

When this creature enters, if you control two or more Islands, you may tap two target permanents.
When this creature enters, if you control two or more Mountains, you may have this creature deal 2 damage to target player or planeswalker.

Everlasting Torment

Players can't gain life.
Damage can't be prevented.
All damage is dealt as though its source had wither. (A source with wither deals damage to creatures in the form of -1/-1 counters.)

Niv-Mizzet, Guildpact

Flying, hexproof from multicolored
Whenever Niv-Mizzet deals combat damage to a player, it deals X damage to any target, target player draws X cards, and you gain X life, where X is the number of different color pairs among permanents you control that are exactly two colors.

Burnwillow Clearing

This land enters tapped.
{T}: Add {R} or {G}.

Stump Stomp

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control.

Stump Stomp // Burnwillow Clearing

Rubblebelt Raiders

Whenever this creature attacks, put a +1/+1 counter on it for each attacking creature you control.

Murderous Redcap

When this creature enters, it deals damage equal to its power to any target.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Mindwrack Liege

Other blue creatures you control get +1/+1.
Other red creatures you control get +1/+1.
{U/R}{U/R}{U/R}{U/R}: You may put a blue or red creature card from your hand onto the battlefield.

Tempest Angler

Whenever you cast a noncreature spell, put a +1/+1 counter on this creature.

Spiteful Banditry

When this enchantment enters, it deals X damage to each creature.
Whenever one or more creatures your opponents control die, you create a Treasure token. This ability triggers only once each turn.

Wild Cantor

({R/G} can be paid with either {R} or {G}.)
Sacrifice this creature: Add one mana of any color.

Vexing Shusher

This spell can't be countered.
{R/G}: Target spell can't be countered.

Tome of the Guildpact

Whenever you cast a multicolored spell, draw a card.
{T}: Add one mana of any color.

Mines of Moria

Mines of Moria enters tapped unless you control a legendary creature.
{T}: Add {R}.
{3}{R}, {T}, Exile three cards from your graveyard: Create two Treasure tokens.

Figure of Destiny

{R/W}: This creature becomes a Kithkin Spirit with base power and toughness 2/2.
{R/W}{R/W}{R/W}: If this creature is a Spirit, it becomes a Kithkin Spirit Warrior with base power and toughness 4/4.
{R/W}{R/W}{R/W}{R/W}{R/W}{R/W}: If this creature is a Warrior, it becomes a Kithkin Spirit Warrior Avatar with base power and toughness 8/8, flying, and first strike.

Boros Reckoner

Whenever this creature is dealt damage, it deals that much damage to any target.
{R/W}: This creature gains first strike until end of turn.

Mana Cannons

Whenever you cast a multicolored spell, this enchantment deals X damage to any target, where X is the number of colors that spell is.

Pirate's Pillage

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Izzet Signet

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Blade Historian

Attacking creatures you control have double strike.

Runes of the Deus

Enchant creature
As long as enchanted creature is red, it gets +1/+1 and has double strike. (It deals both first-strike and regular combat damage.)
As long as enchanted creature is green, it gets +1/+1 and has trample.

Ashenmoor Liege

Other black creatures you control get +1/+1.
Other red creatures you control get +1/+1.
Whenever this creature becomes the target of a spell or ability an opponent controls, that player loses 4 life.

Balefire Liege

Other red creatures you control get +1/+1.
Other white creatures you control get +1/+1.
Whenever you cast a red spell, this creature deals 3 damage to target player or planeswalker.
Whenever you cast a white spell, you gain 3 life.

Spiteful Visions

At the beginning of each player's draw step, that player draws an additional card.
Whenever a player draws a card, this enchantment deals 1 damage to that player.

Great Hall of the Citadel

{T}: Add {C}.
{1}, {T}: Add two mana in any combination of colors. Spend this mana only to cast legendary spells.

Elite Headhunter

Menace (This creature can't be blocked except by two or more creatures.)
{B/R}{B/R}{B/R}, Sacrifice another creature or an artifact: This creature deals 2 damage to target creature or planeswalker.

Ecstatic Electromancer

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever this creature enters or attacks, you may discard a card. If you do, draw a card.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Boros Signet

Hearthfire Hobgoblin

Footlight Fiend

When this creature dies, it deals 1 damage to any target.

Furious Spinesplitter

Trample
At the beginning of your end step, put a +1/+1 counter on this creature for each opponent who was dealt damage this turn.

Arrows of Justice

Arrows of Justice deals 4 damage to target attacking or blocking creature.

Ruby Medallion

Red spells you cast cost {1} less to cast.

Fanatic of Mogis

When this creature enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Dominus of Fealty

Flying
At the beginning of your upkeep, you may gain control of target permanent until end of turn. If you do, untap it and it gains haste until end of turn.

Gruul Signet

Boartusk Liege

Trample
Other red creatures you control get +1/+1.
Other green creatures you control get +1/+1.

Cryptborn Horror

Trample
This creature enters with X +1/+1 counters on it, where X is the total life lost by your opponents this turn.

Pit Fight

Target creature you control fights another target creature. (Each deals damage equal to its power to the other.)

Professional Face-Breaker

Menace
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Sacrifice a Treasure: Exile the top card of your library. You may play that card this turn.

Rakdos Signet

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Koth, Fire of Resistance

+2: Search your library for a basic Mountain card, reveal it, put it into your hand, then shuffle.
−3: Koth deals damage to target creature equal to the number of Mountains you control.
−7: You get an emblem with "Whenever a Mountain you control enters, this emblem deals 4 damage to any target."

Castle Embereth

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

Samut, Tyrant Smasher

Creatures you control have haste.
−1: Target creature gets +2/+1 and gains haste until end of turn. Scry 1.

Chandra, Roaring Flame

+1: Chandra deals 2 damage to target player or planeswalker.
−2: Chandra deals 2 damage to target creature.
−7: Chandra deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra.
{T}: Chandra deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

Noggle Bandit

This creature can't be blocked except by creatures with defender.

Arena of Glory

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert this land: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Waves of Aggression

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Defiler of Instinct

First strike
As an additional cost to cast red permanent spells, you may pay 2 life. Those spells cost {R} less to cast if you paid life this way. This effect reduces only the amount of red mana you pay.
Whenever you cast a red permanent spell, this creature deals 1 damage to any target.

Nobilis of War

Flying
Attacking creatures you control get +2/+0.

Big Score

Fists of the Demigod

Enchant creature
As long as enchanted creature is black, it gets +1/+1 and has wither. (It deals damage to creatures in the form of -1/-1 counters.)
As long as enchanted creature is red, it gets +1/+1 and has first strike.

Arcane Signet

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

Crackling Falls

This land enters tapped.
{T}: Add {U} or {R}.

Rush of Inspiration

Draw two cards. Then discard a card at random unless you pay {E}{E} (two energy counters).

Rush of Inspiration // Crackling Falls

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.