Eland Umbra

Enchant creature
Enchanted creature gets +0/+4.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

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.

Molten Tributary

({T}: Add {U} or {R}.)
Molten Tributary enters the battlefield tapped.

Chop Down

Destroy target creature with power 4 or greater. (Then exile this card. You may cast the creature later from exile.)

Giant Killer

Giant Killer // Chop Down

Temple of Enlightenment

Temple of Enlightenment enters the battlefield tapped.
When Temple of Enlightenment enters the battlefield, scry 1.
{T}: Add {W} or {U}.

Bastion Protector

Commander creatures you control get +2/+2 and have indestructible.

Nin, the Pain Artist

{X}{U}{R}, {T}: Nin, the Pain Artist deals X damage to target creature. That creature's controller draws X cards.

Of One Mind

This spell costs {2} less to cast if you control a Human creature and a non-Human creature.
Draw two cards.

Solar Blaze

Each creature deals damage to itself equal to its power.

Silverbluff Bridge

Silverbluff Bridge enters the battlefield tapped.
Indestructible
{T}: Add {U} or {R}.

Command Tower

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

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Howlpack Avenger

Whenever a permanent you control is dealt damage, Howlpack Avenger deals that much damage to any target.
{1}{R}: Howlpack Avenger gets +2/+0 until end of turn.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Ill-Tempered Loner

Whenever Ill-Tempered Loner is dealt damage, it deals that much damage to any target.
{1}{R}: Ill-Tempered Loner gets +2/+0 until end of turn.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Ill-Tempered Loner // Howlpack Avenger

Truefire Captain

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Truefire Captain is dealt damage, it deals that much damage to target player.

Palisade Giant

All damage that would be dealt to you and other permanents you control is dealt to Palisade Giant instead.

Island

Wandering Fumarole

Wandering Fumarole enters the battlefield tapped.
{T}: Add {U} or {R}.
{2}{U}{R}: Until end of turn, Wandering Fumarole becomes a 1/4 blue and red Elemental creature with "{0}: Switch this creature's power and toughness until end of turn." It's still a land.

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Deafening Clarion

Choose one or both —
• Deafening Clarion deals 3 damage to each creature.
• Creatures you control gain lifelink until end of turn.

Abrade

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

Fell the Mighty

Destroy all creatures with power greater than target creature's power.

Tamiyo's Epiphany

Temple of Triumph

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

Witness Protection

Enchant creature
Enchanted creature loses all abilities and is a green and white Citizen creature with base power and toughness 1/1 named Legitimate Businessperson. (It loses all other colors, card types, creature types, and names.)

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Crib Swap

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

No More

Any number of target creatures you control phase out.
Fuse (You may cast one or both halves of this card from your hand.)

Gallifrey Falls

Gallifrey Falls deals 4 damage to each creature. If a creature dealt damage this way would die this turn, exile it instead.
Fuse (You may cast one or both halves of this card from your hand.)

Gallifrey Falls // No More

Boros Signet

Plains

Ferrous Lake

Mountain

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Frostboil Snarl

As Frostboil Snarl enters the battlefield, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters the battlefield tapped.
{T}: Add {U} or {R}.

Azorius Signet

Darksteel Myr

Indestructible (Damage and effects that say "destroy" don't destroy this creature. If its toughness is 0 or less, it's still put into its owner's graveyard.)

Arcbond

Choose target creature. Whenever that creature is dealt damage this turn, it deals that much damage to each other creature and each player.

Cathar Commando

Flash
{1}, Sacrifice Cathar Commando: Destroy target artifact or enchantment.

Precognitive Perception

Draw three cards.
Addendum — If you cast this spell during your main phase, instead scry 3, then draw three cards.

The Seventh Doctor

Whenever The Seventh Doctor attacks, choose a card in your hand. Defending player guesses whether that card's mana value is greater than the number of artifacts you control. If they guessed wrong, you may cast it without paying its mana cost. If you don't cast a spell this way, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Sacred Peaks

({T}: Add {R} or {W}.)
Sacred Peaks enters the battlefield tapped.

Mystic Confluence

Choose three. You may choose the same mode more than once.
• Counter target spell unless its controller pays {3}.
• Return target creature to its owner's hand.
• Draw a card.

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.")

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Saw It Coming

Counter target spell.
Foretell {1}{U} (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.)

Heartflame Slash

Heartflame Slash deals 3 damage to any target. (Then exile this card. You may cast the creature later from exile.)

Heartflame Duelist

Instant and sorcery spells you control have lifelink.

Heartflame Duelist // Heartflame Slash

Negate

Fateful Absence

Destroy target creature or planeswalker. Its controller investigates. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Port Town

As Port Town enters the battlefield, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters the battlefield tapped.
{T}: Add {W} or {U}.

Rewind

Counter target spell. Untap up to four lands.

Mystic Monastery

Mystic Monastery enters the battlefield tapped.
{T}: Add {U}, {R}, or {W}.

Boros Garrison

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

Fiery Confluence

Choose three. You may choose the same mode more than once.
• Fiery Confluence deals 1 damage to each creature.
• Fiery Confluence deals 2 damage to each opponent.
• Destroy target artifact.

Deflecting Palm

The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

Into the Fire

Choose one —
• Into the Fire deals 2 damage to each creature, planeswalker, and battle.
• Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Illusory Ambusher

Flash (You may cast this spell any time you could cast an instant.)
Whenever Illusory Ambusher is dealt damage, draw that many cards.

Arwen's Gift

This spell costs {1} less to cast if you control two or more legendary creatures.
Scry 2, then draw two cards.

Furycalm Snarl

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

Anger of the Gods

Anger of the Gods deals 3 damage to each creature. If a creature dealt damage this way would die this turn, exile it instead.

Talisman of Conviction

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

Izzet Signet

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Generous Gift

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

Guilty Conscience

Enchant creature
Whenever enchanted creature deals damage, Guilty Conscience deals that much damage to that creature.

Valorous Stance

Choose one —
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
• Destroy target creature with toughness 4 or greater.

Mana Leak

Counter target spell unless its controller pays {3}.

Skycloud Expanse

Donna Noble

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
Whenever Donna or a creature it's paired with is dealt damage, Donna deals that much damage to target opponent.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Justice Strike

Target creature deals damage to itself equal to its power.

Spitemare

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

Saving Grace

Flash
Enchant creature you control
When Saving Grace enters the battlefield, all damage that would be dealt this turn to you and permanents you control is dealt to enchanted creature instead.
Enchanted creature gets +0/+3.

Idyllic Beachfront

({T}: Add {W} or {U}.)
Idyllic Beachfront enters the battlefield tapped.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Mercurial Chemister

{U}, {T}: Draw two cards.
{R}, {T}, Discard a card: Mercurial Chemister deals damage to target creature equal to the discarded card's mana value.

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Behold the Multiverse

Scry 2, then draw two cards.
Foretell {1}{U} (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.)

Boros Reckoner

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

Gideon's Sacrifice

Choose a creature or planeswalker you control. All damage that would be dealt this turn to you and permanents you control is dealt to the chosen permanent instead (if it's still on the battlefield).

Celestial Colonnade

Celestial Colonnade enters the battlefield tapped.
{T}: Add {W} or {U}.
{3}{W}{U}: Until end of turn, Celestial Colonnade becomes a 4/4 white and blue Elemental creature with flying and vigilance. It's still a land.