Whenever a player plays a spell that counters a spell that has been played or a player plays a spell that comes into play with counters, that player may counter the next spell played or put an additional counter on a permanent that has already been played, but not countered.

Flash

Enchant instant or sorcery spell on the stack

When Animate Spell becomes attached to an instant or sorcery, put that card onto the battlefield under its owner's control. It's a creature in addition to its other types with power and toughness each equal to its converted mana cost.

When Animate Spell leaves the battlefield, enchanted card's owner sacrifices it unless they cast it.

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

Flying, deathtouch

When Baleful Strix enters the battlefield, draw a card.

Spells you cast cost {1} less to cast.

You must speak in a voice other than your normal voice.

When you speak in your normal voice, sacrifice Bronze Calendar.

Callaphe's power is equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Creatures and enchantments you control have "Spells your opponents cast that target this permanent cost {1} more to cast."

As Censorship enters the battlefield, choose a word.

Whenever a player says the chosen word, Censorship deals 2 damage to that player.

Charcoal Diamond enters the battlefield tapped.

{T}: Add {B}.

Cast this spell only if there are three or more players in the game.

Whenever a player casts a spell, each of that player's opponents may discard a card. If they do, counter that spell.

Lands you control have "{T}: Add one mana of any color."

{T}: Add one mana of any color.

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.

{T}: Add {U}.

{T}: Add {B}.

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

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

Sacrifice Commander's Sphere: Draw a card.

Whenever a player casts a spell without asking your permission while casting it, counter that spell.

When a player asks you permission to cast a spell and you refuse, counter that spell and sacrifice Common Courtesy.

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.

Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

{4}, Sacrifice Copper Gnomes: You may put an artifact card from your hand onto the battlefield.

Enchant creature

{2}{U}: Untap enchanted creature.

Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Destroy all creatures. They can't be regenerated.

{1}, {T}: Add {U}{B}.

Dimir Aqueduct enters the battlefield tapped.

When Dimir Aqueduct enters the battlefield, return a land you control to its owner's hand.

{T}: Add {U}{B}.

{1}, {T}: Add {U}{B}.

Dismal Backwater enters the battlefield tapped.

When Dismal Backwater enters the battlefield, you gain 1 life.

{T}: Add {U} or {B}.

Domesticated Watercourse enters the battlefield tapped.

{T}: Add {U} or {B}.

{U}{B}: Until end of turn, Domesticated Watercourse becomes an Equipment artifact with equip {2}.

Whenever equipped creature deals combat damage to a player, draw a card.

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp.

{T}: Add {U} or {B}.

Everlasting Lich can't block.

Everlasting Lich can't die. (This creature has indestructible, can't be sacrificed, and doesn't go to the graveyard for having 0 toughness.)

{1}, {T}: Scry 2.

{1}, {T}, Pay 1 life: Create a 0/1 white Goat creature token.

{7}, {T}, Sacrifice Everythingamajig: Choose target player. At the beginning of the next end step, exchange life totals with that player, exchange control of all permanents you and that player control, and exchange cards in your hands, cards in your libraries, and cards in your graveyards.

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

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

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

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

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

When Free-for-All enters the battlefield, exile all creatures face down.

At the beginning of each player's upkeep, that player chooses a card exiled with Free-for-All at random and puts it onto the battlefield.

When Free-for-All leaves the battlefield, put all cards exiled with it into their owners' graveyards.

Whenever Hammer of Nazahn or another Equipment enters the battlefield under your control, you may attach that Equipment to target creature you control.

Equipped creature gets +2/+0 and has indestructible.

Equip {4}

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

({T}: Add {U} or {B}.)

Ice Tunnel enters the battlefield tapped.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

{4}: Search your library for a card, put that card into your hand, then shuffle.

Jwar Isle Refuge enters the battlefield tapped.

When Jwar Isle Refuge enters the battlefield, you gain 1 life.

{T}: Add {U} or {B}.

Destroy target nonblack creature.

Gotcha -- If an opponent says "kill" or "destroy," you may say "Gotcha!" When you do, return Kill! Destroy! from your graveyard to your hand.

{U}: Change the text of target spell or permanent by replacing all instances of + with -, and vice versa, until end of turn.

Manascape Refractor enters the battlefield tapped.

Manascape Refractor has all activated abilities of all lands on the battlefield.

You may spend mana as though it were mana of any color to pay the activation costs of Manascape Refractor's abilities.

{U}, {T}, Return an artifact you control to its owner's hand: You may put an artifact card from your hand onto the battlefield.

Mirror Mirror enters the battlefield tapped.

{7}, {T}, Sacrifice Mirror Mirror: Choose target player. At the beginning of the next end step, exchange life totals with that player, exchange control of all permanents you and that player control, and exchange cards in your hands, cards in your libraries, and cards in your graveyards.

Add or subtract 1 or one from a number or number word on target spell or permanent until end of turn.

Myriad Landscape enters the battlefield tapped.

{T}: Add {C}.

{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Flying, deathtouch, lifelink

Nighthawk Scavenger's power is equal to 1 plus the number of card types among cards in your opponents' graveyards.

Flying, deathtouch

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Return target permanent to its owner's hand.

Gotcha -- If an opponent says a number, you may say "Gotcha!" When you do, return Number Crunch from your graveyard to your hand.

Whenever a creature deals damage to a player, that player may say "Ow" once for each permanent named Ow. If the player doesn't, Ow deals 1 damage to them.

Enchant creature

Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)

Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

Phoebe, Head of S.N.E.A.K. can't be blocked by creatures with flavor text.

{2}{U}{B}: Phoebe permanently steals target creature's text box. (That creature loses all rules text, flavor text, and watermarks. This creature gains them.)

Look at the top three cards of your library, then put them back in any order. You may shuffle.

Draw a card.

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

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

Enchant creature

Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)

Whenever enchanted creature attacks, you scry 2.

Each player plays with the top card of their library held against their forehead, revealed to each other player.

You may play cards as though they were other cards of your choice with the same mana cost. You can't choose the same card twice. (Mana cost includes color.)

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)

Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Shambling Suit's power is equal to the number of artifacts and/or enchantments you control.

Sky Diamond enters the battlefield tapped.

{T}: Add {U}.

{T}: Add {C}{C}.

Counter target spell.

Gotcha -- If an opponent says "spell" or "counter," you may say "Gotcha!" When you do, return Spell Counter from your graveyard to your hand.

When Split Screen enters the battlefield, shuffle your library and deal it into four libraries. If anything refers to your library, choose one of your libraries for it.

Play with your libraries' top cards revealed.

When Split Screen leaves the battlefield, shuffle your libraries together.

({T}: Add {U} or {B}.)

Sunken Hollow enters the battlefield tapped unless you control two or more basic lands.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

Temple of Deceit enters the battlefield tapped.

When Temple of Deceit enters the battlefield, scry 1.

{T}: Add {U} or {B}.

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

{T}: Add {C}{C}{C}.

The phases of each player's turn are reversed. (The phases are, in reverse order, ending, postcombat main, combat, precombat main, and beginning.)

As long as there are more than two players in the game, the turn order is reversed.

Creatures entering the battlefield don't cause abilities to trigger.

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

{T}: Add {C}.

{T}: Add one mana of any color. Spend this mana only to pay Un-costs.

{T}: Add {C}.

{T}: Add {U} or {B}. Underground River deals 1 damage to you.

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

Urza's Contact Lenses enters the battlefield tapped.

Urza's Contact Lenses doesn't untap during your untap step.

As long as Urza's Contact Lenses is untapped, all players play with their hands revealed.

Clap your hands twice: You may tap or untap Urza's Contact Lenses.

Enchant creature

{U}{U}: Enchanted creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Enchant creature

Enchanted creature gets +2/+2, has flying, and can't attack you or planeswalkers you control.

As Water Gun Balloon Game enters the battlefield, each player puts a pop! counter on "0."

Whenever a player casts a spell, move that player's pop! counter up one.

Whenever a player's pop! counter hits "5," that player creates a 5/5 pink Giant Teddy Bear creature token and resets all pop! counters to "0."

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

{3}{B}: Until end of turn, Xathrid Slyblade loses hexproof and gains first strike and deathtouch. (It deals combat damage before creatures without first strike. Any amount of damage it deals to a creature is enough to destroy it.)