Mourner's Shield

Imprint — When Mourner's Shield enters, you may exile target card from a graveyard.
{2}, {T}: Prevent all damage that would be dealt this turn by a source of your choice that shares a color with the exiled card.

Mana Maze

Players can't cast spells that share a color with the spell most recently cast this turn.

Govern the Guildless

Gain control of target monocolored creature.
Forecast — {1}{U}, Reveal Govern the Guildless from your hand: Target creature becomes the color or colors of your choice until end of turn. (Activate only during your upkeep and only once each turn.)

Glaciers

At the beginning of your upkeep, sacrifice Glaciers unless you pay {W}{U}.
All Mountains are Plains.

Radiant, Serra Archangel

Flying
Tap another untapped creature you control with flying: Radiant, Serra Archangel gains protection from the color of your choice until end of turn.
Partner (You can have two commanders if both have partner.)

Hunting Drake

Flying
When Hunting Drake enters, put target red or green creature on top of its owner's library.

Lawbringer

{T}, Sacrifice Lawbringer: Exile target red creature.

Wrath of Marit Lage

When Wrath of Marit Lage enters, tap all red creatures.
Red creatures don't untap during their controllers' untap steps.

Story Circle

As Story Circle enters, choose a color.
{W}: The next time a source of your choice of the chosen color would deal damage to you this turn, prevent that damage.

Frazzle

Royal Decree

Cumulative upkeep {W} (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.)
Whenever a Swamp, Mountain, black permanent, or red permanent becomes tapped, Royal Decree deals 1 damage to that permanent's controller.

Conversion

At the beginning of your upkeep, sacrifice Conversion unless you pay {W}{W}.
All Mountains are Plains.

Benevolent Blessing

Flash
Enchant creature
As Benevolent Blessing enters, choose a color.
Enchanted creature has protection from the chosen color. This effect doesn't remove Auras and Equipment you control that are already attached to it.

Flash Flood

Choose one —
• Destroy target red permanent.
• Return target Mountain to its owner's hand.

Mangara's Equity

As Mangara's Equity enters, choose black or red.
At the beginning of your upkeep, sacrifice Mangara's Equity unless you pay {1}{W}.
Whenever a creature of the chosen color deals damage to you or a white creature you control, Mangara's Equity deals that much damage to that creature.

High Seas

Red creature spells and green creature spells cost {1} more to cast.

Surge of Righteousness

Destroy target black or red creature that's attacking or blocking. You gain 2 life.

Shield Mare

Shield Mare can't be blocked by red creatures.
When Shield Mare enters or becomes the target of a spell or ability an opponent controls, you gain 3 life.

Rune of Protection: Red

{W}: The next time a red source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)

Lightwielder Paladin

First strike (This creature deals combat damage before creatures without first strike.)
Whenever Lightwielder Paladin deals combat damage to a player, you may exile target black or red permanent that player controls.

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Thought Prison

Imprint — When Thought Prison enters, you may have target player reveal their hand. If you do, choose a nonland card from it and exile that card.
Whenever a player casts a spell that shares a color or mana value with the exiled card, Thought Prison deals 2 damage to that player.

Aether Gust

Choose target spell or permanent that's red or green. Its owner puts it on their choice of the top or bottom of their library.

Douse

Sejiri Glacier

Sejiri Glacier enters tapped.
{T}: Add {W}.

Sejiri Shelter

Target creature you control gains protection from the color of your choice until end of turn.

Sejiri Shelter // Sejiri Glacier

Honorable Passage

The next time a source of your choice would deal damage to any target this turn, prevent that damage. If damage from a red source is prevented this way, Honorable Passage deals that much damage to the source's controller.

Hydroblast

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

Devout Decree

Exile target creature or planeswalker that's black or red. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Volcanic Eruption

Destroy X target Mountains. Volcanic Eruption deals damage to each creature and each player equal to the number of Mountains put into a graveyard this way.

Justice

At the beginning of your upkeep, sacrifice Justice unless you pay {W}{W}.
Whenever a red creature or spell deals damage, Justice deals that much damage to that creature's or spell's controller.

Celestial Purge

Blue Elemental Blast

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

Encase in Ice

Flash (You may cast this spell any time you could cast an instant.)
Enchant red or green creature
When Encase in Ice enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Ivory Giant

When Ivory Giant enters, tap all nonwhite creatures.
Suspend 5—{W} (Rather than cast this card from your hand, you may pay {W} and exile it with five 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. It has haste.)

Sphere of Law

If a red source would deal damage to you, prevent 2 of that damage.

Harsh Judgment

As Harsh Judgment enters, choose a color.
If an instant or sorcery spell of the chosen color would deal damage to you, it deals that damage to its controller instead.

Tidal Control

Cumulative upkeep {2} (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.)
Pay 2 life or {2}: Counter target red or green spell. Any player may activate this ability.

Chill

Plains

Mass Calcify

Greater Realm of Preservation

{1}{W}: The next time a black or red source of your choice would deal damage to you this turn, prevent that damage.

Sanctimony

Whenever an opponent taps a Mountain for mana, you may gain 1 life.

Circle of Protection: Red

{1}: The next time a red source of your choice would deal damage to you this turn, prevent that damage.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Southern Paladin

{W}{W}, {T}: Destroy target red permanent.

Floodgate

Defender
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Teferi's Moat

As Teferi's Moat enters, choose a color.
Creatures of the chosen color without flying can't attack you.