Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Whenever you cast a permanent spell with a mana cost that contains {X}, double the value of X. Whenever you cast an instant or sorcery spell or activate an ability, if that spell's mana cost or that ability's activation cost contains {X}, copy that spell or ability. You may choose new targets for the copy.

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order. Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Join forces — Starting with you, each player may pay any amount of mana. Each player searches their library for up to X basic land cards, where X is the total amount of mana paid this way, puts them onto the battlefield tapped, then shuffles.

You may play an additional land on each of your turns. Lands you control are every basic land type in addition to their other types.

Whenever you cast a spell with {X} in its mana cost, put two charge counters on this artifact. {T}: Add one mana of any color. {T}: Add {C} for each charge counter on this artifact. Spend this mana only on costs that contain {X}.

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.) This artifact enters with a charge counter on it for each time it was kicked. {T}: Add {C} for each charge counter on this artifact.

As this enchantment enters, choose Khans or Dragons. • Khans — At the beginning of each of your main phases, add {G}{G}. • Dragons — Whenever a creature you control with flying enters, you may have it fight target creature you don't control.

Each spell you cast that's red or green costs {1} less to cast.

{X}, {T}: Untap X target lands.

Each player may search their library for up to X basic land cards and put them onto the battlefield tapped. Then each player who searched their library this way shuffles.

Choose one — • Search your library for up to X land cards, reveal them, put them into your hand, then shuffle. • Nylea's Intervention deals twice X damage to each creature with flying.

{T}: Add {R}. When that mana is spent to cast a red instant or sorcery spell, copy that spell and you may choose new targets for the copy.

{T}: Add {C}{C}{C}{C}. Spend this mana only on costs that contain {X}.

This spell costs {1} less to cast for each creature on the battlefield. Blasphemous Act deals 13 damage to each creature.

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

Earthquake deals X damage to each creature without flying and each player.

All creatures lose indestructible until end of turn. Hour of Devastation deals 5 damage to each creature and each non-Bolas planeswalker.

Choose one. If you control a commander as you cast this spell, you may choose both instead. • Breathe Flame — Klauth's Will deals X damage to each creature without flying. • Smash Relics — Destroy up to X target artifacts and/or enchantments.

Destroy up to X target artifacts and/or enchantments. Create twice X 1/1 black and green Pest creature tokens with "When this token dies, you gain 1 life."

Subterranean Tremors deals X damage to each creature without flying. If X is 4 or more, destroy all artifacts. If X is 8 or more, create an 8/8 red Lizard creature token.

Create X X/X green Ooze creature tokens.

As this creature enters, roll X d6. It enters with a number of +1/+1 counters on it equal to the total of those results. Trample Ward {4} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)

Trample This creature enters with X +1/+1 counters on it. Split — When this creature dies, if it had two or more +1/+1 counters on it, create a token that's a copy of it at the beginning of the next end step. The token enters with half that many +1/+1 counters on it, rounded down.

({T}: Add {R} or {G}.) This land enters tapped unless you control two or more basic lands.

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

({T}: Add {G}.)

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

{T}: Add {C}. {X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

({T}: Add {R}.)

{T}: Add {C}. {2}, {T}, Sacrifice a Desert: Exile all graveyards.

({T}: Add {R} or {G}.) This land enters tapped. Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {R} or {G}.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

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}.

Cumulative upkeep—Add {R}. (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.)

+1: Add {R} or {G}. If that mana is spent on a creature spell, it gains riot. (It enters with your choice of a +1/+1 counter or haste.) −3: Look at the top four cards of your library. You may reveal up to two creature cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order. −8: You get an emblem with "At the beginning of each end step, create a 4/4 red and green Beast creature token with trample."

Add seven {R}. You can cast only one more spell this turn.

+1: Add {R}{R}{R}. Spend this mana only to cast instant or sorcery spells. +1: Discard up to three cards, then draw that many cards. −8: You get an emblem with "You may cast instant and sorcery spells from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead."

Add {R} for each tapped land your opponents control.

Flying Whenever this creature attacks, add {R}{R}{R}{G}{G}{G}. Until end of turn, you don't lose this mana as steps and phases end.

Banefire deals X damage to any target. If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.) Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Crackle with Power deals five times X damage to each of up to X targets.

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Flash Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Untap all permanents you control during each other player's untap step.

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.

Strive — This spell costs {2}{G} more to cast for each target beyond the first. Destroy any number of target artifacts and/or enchantments.

Exile the top seven cards of your library. Until end of turn, you may cast spells from among them. If this spell was cast from your hand, add ten mana of any one color.

+1: Discard your hand, then exile the top three cards of your library. Until end of turn, you may play cards exiled this way. +1: Chandra deals 2 damage to any target. −9: Search your graveyard and library for any number of red instant and/or sorcery cards, exile them, then shuffle. You may cast them this turn. Add six {R}.

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

You may look at the top card of your library any time. You may play lands and cast spells from the top of your library. You can't play lands or cast spells from your hand. {3}{R}: Destroy this enchantment.

As this enchantment enters, choose Khans or Dragons. • Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card. • Dragons — Whenever a creature you control leaves the battlefield, this enchantment deals 1 damage to any target.

{2}: Put a charge counter on this artifact. Remove a charge counter from this artifact: Add one mana of any color.

If you would lose unspent mana, that mana becomes colorless instead.

Flying You don't lose unspent red mana as steps and phases end. When this creature dies, you may pay any amount of {R}. When you do, it deals that much damage to any target.

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}

Permanents you control gain hexproof and indestructible until end of turn.

Return X cards at random from your graveyard to your hand. Exile Reap the Past.

Creature spells you control can't be countered. Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)