Impulsive Maneuvers

Whenever a creature attacks, flip a coin. If you win the flip, the next time that creature would deal combat damage this turn, it deals double that damage instead. If you lose the flip, the next time that creature would deal combat damage this turn, prevent that damage.

Mountain

Comeuppance

Prevent all damage that would be dealt to you and planeswalkers you control this turn by sources you don't control. If damage from a creature source is prevented this way, Comeuppance deals that much damage to that creature. If damage from a noncreature source is prevented this way, Comeuppance deals that much damage to the source's controller.

Bitter Feud

As Bitter Feud enters, choose two players.
If a source controlled by one of the chosen players would deal damage to the other chosen player or a permanent that player controls, that source deals double that damage to that player or permanent instead.

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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.

Spike Weaver

Spike Weaver enters with three +1/+1 counters on it.
{2}, Remove a +1/+1 counter from Spike Weaver: Put a +1/+1 counter on target creature.
{1}, Remove a +1/+1 counter from Spike Weaver: Prevent all combat damage that would be dealt this turn.

Holy Day

Prevent all combat damage that would be dealt this turn.

Nomad Outpost

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

Angelsong

Prevent all combat damage that would be dealt this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Indatha Triome

({T}: Add {W}, {B}, or {G}.)
Indatha Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Markov Blademaster

Double strike
Whenever Markov Blademaster deals combat damage to a player, put a +1/+1 counter on it.

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Savage Lands

Savage Lands enters tapped.
{T}: Add {B}, {R}, or {G}.

Darkness

Gideon of the Trials

+1: Until your next turn, prevent all damage target permanent would deal.
0: Until end of turn, Gideon of the Trials becomes a 4/4 Human Soldier creature with indestructible that's still a planeswalker. Prevent all damage that would be dealt to him this turn.
0: You get an emblem with "As long as you control a Gideon planeswalker, you can't lose the game and your opponents can't win the game."

Moment's Peace

Prevent all combat damage that would be dealt this turn.
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dawn Charm

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

Overblaze

Each time target permanent would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.
Splice onto Arcane {2}{R}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Knight-Captain of Eos

When Knight-Captain of Eos enters, create two 1/1 white Soldier creature tokens.
{W}, Sacrifice a Soldier: Prevent all combat damage that would be dealt this turn.

Gisela, Blade of Goldnight

Flying, first strike
If a source would deal damage to an opponent or a permanent an opponent controls, that source deals double that damage to that player or permanent instead.
If a source would deal damage to you or a permanent you control, prevent half that damage, rounded up.

Sphere of Safety

Creatures can't attack you or planeswalkers you control unless their controller pays {X} for each of those creatures, where X is the number of enchantments you control.

Prismatic Vista

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Mystic Monastery

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

Druid's Deliverance

Prevent all combat damage that would be dealt to you this turn. Populate. (Create a token that's a copy of a creature token you control.)

Quest for Pure Flame

Whenever a source you control deals damage to an opponent, you may put a quest counter on Quest for Pure Flame.
Remove four quest counters from Quest for Pure Flame and sacrifice it: If any source you control would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Solitary Confinement

At the beginning of your upkeep, sacrifice Solitary Confinement unless you discard a card.
Skip your draw step.
You have shroud. (You can't be the target of spells or abilities.)
Prevent all damage that would be dealt to you.

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Idyllic Tutor

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

Arcane Sanctum

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Jungle Shrine

Jungle Shrine enters tapped.
{T}: Add {R}, {G}, or {W}.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Arachnogenesis

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Raugrin Triome

({T}: Add {U}, {R}, or {W}.)
Raugrin Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Propaganda

Sandsteppe Citadel

Sandsteppe Citadel enters tapped.
{T}: Add {W}, {B}, or {G}.

Plains

Exotic Orchard

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

Spore Frog

Sacrifice Spore Frog: Prevent all combat damage that would be dealt this turn.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Maze of Ith

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

Dromoka's Command

Choose two —
• Prevent all damage target instant or sorcery spell would deal this turn.
• Target player sacrifices an enchantment.
• Put a +1/+1 counter on target creature.
• Target creature you control fights target creature you don't control.

Solemnity

Players can't get counters.
Counters can't be put on artifacts, creatures, enchantments, or lands.

Phyrexian Unlife

You don't lose the game for having 0 or less life.
As long as you have 0 or less life, all damage is dealt to you as though its source had infect. (Damage is dealt to you in the form of poison counters.)

Gideon Jura

+2: During target opponent's next turn, creatures that player controls attack Gideon Jura if able.
−2: Destroy target tapped creature.
0: Until end of turn, Gideon Jura becomes a 6/6 Human Soldier creature that's still a planeswalker. Prevent all damage that would be dealt to him this turn.

Dawnstrider

{G}, {T}, Discard a card: Prevent all combat damage that would be dealt this turn.

Rites of Flourishing

At the beginning of each player's draw step, that player draws an additional card.
Each player may play an additional land on each of their turns.

Tangle

Prevent all combat damage that would be dealt this turn.
Each attacking creature doesn't untap during its controller's next untap step.

Enduring Ideal

Search your library for an enchantment card, put it onto the battlefield, then shuffle.
Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps, copy this spell except for its epic ability.)

Kiora, the Crashing Wave

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.
−1: Draw a card. You may play an additional land this turn.
−5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

Intervention Pact

The next time a source of your choice would deal damage to you this turn, prevent that damage. You gain life equal to the damage prevented this way.
At the beginning of your next upkeep, pay {1}{W}{W}. If you don't, you lose the game.

Kruphix, God of Horizons

Indestructible
As long as your devotion to green and blue is less than seven, Kruphix isn't a creature.
You have no maximum hand size.
If you would lose unspent mana, that mana becomes colorless instead.

Savai Triome

({T}: Add {R}, {W}, or {B}.)
Savai Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Ethereal Haze

Prevent all damage that would be dealt by creatures this turn.

Pir's Whim

For each player, choose friend or foe. Each friend searches their library for a land card, puts it onto the battlefield tapped, then shuffles. Each foe sacrifices an artifact or enchantment they control.

Forest

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Fog Bank

Defender, flying
Prevent all combat damage that would be dealt to and dealt by Fog Bank.

Obscuring Haze

If you control a commander, you may cast this spell without paying its mana cost.
Prevent all damage that would be dealt this turn by creatures your opponents control.

Psychic Possession

Enchant opponent
Skip your draw step.
Whenever enchanted opponent draws a card, you may draw a card.

Island

Dovin, Hand of Control

Artifact, instant, and sorcery spells your opponents cast cost {1} more to cast.
−1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.

Prophetic Flamespeaker

Double strike, trample
Whenever Prophetic Flamespeaker deals combat damage to a player, exile the top card of your library. You may play it this turn.

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Riot Control

You gain 1 life for each creature your opponents control. Prevent all damage that would be dealt to you this turn.

Glacial Chasm

Cumulative upkeep—Pay 2 life. (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.)
When Glacial Chasm enters, sacrifice a land.
Creatures you control can't attack.
Prevent all damage that would be dealt to you.

Constant Mists

Buyback—Sacrifice a land. (You may sacrifice a land in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Prevent all combat damage that would be dealt this turn.

Orbs of Warding

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
If a creature would deal damage to you, prevent 1 of that damage.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Standstill

When a player casts a spell, sacrifice Standstill. If you do, each of that player's opponents draws three cards.

Kami of False Hope

Sacrifice Kami of False Hope: Prevent all combat damage that would be dealt this turn.

Prismatic Strands

Prevent all damage that sources of the color of your choice would deal this turn.
Flashback—Tap an untapped white creature you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Fiendish Duo

First strike
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Kor Haven

{T}: Add {C}.
{1}{W}, {T}: Prevent all combat damage that would be dealt by target attacking creature this turn.

Selfless Squire

Flash
When Selfless Squire enters, prevent all damage that would be dealt to you this turn.
Whenever damage that would be dealt to you is prevented, put that many +1/+1 counters on Selfless Squire.

Command Tower

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

Batwing Brume

Prevent all combat damage that would be dealt this turn if {W} was spent to cast this spell. Each player loses 1 life for each attacking creature they control if {B} was spent to cast this spell. (Do both if {W}{B} was spent.)

Goblin Goliath

When Goblin Goliath enters, create a number of 1/1 red Goblin creature tokens equal to the number of opponents you have.
{3}{R}, {T}: If a source you control would deal damage to an opponent this turn, it deals double that damage to that player instead.

Zagoth Triome

({T}: Add {B}, {G}, or {U}.)
Zagoth Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Frontier Bivouac

Frontier Bivouac enters tapped.
{T}: Add {G}, {U}, or {R}.

Windswept Heath

{T}, Pay 1 life, Sacrifice Windswept Heath: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Dark Sphere

{T}, Sacrifice Dark Sphere: The next time a source of your choice would deal damage to you this turn, prevent half that damage, rounded down.

Energy Field

Prevent all damage that would be dealt to you by sources you don't control.
When a card is put into your graveyard from anywhere, sacrifice Energy Field.

Swamp

Angrath's Marauders

If a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Crumbling Necropolis

Crumbling Necropolis enters tapped.
{T}: Add {U}, {B}, or {R}.

Winds of Qal Sisma

Prevent all combat damage that would be dealt this turn.
Ferocious — If you control a creature with power 4 or greater, instead prevent all combat damage that would be dealt this turn by creatures your opponents control.