Counterspell

Orvar, the All-Form

Changeling
Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.
When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Fellwar Stone

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

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Gigadrowse

Replicate {U} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Tap target permanent.

Dream's Grip

Choose one —
• Tap target permanent.
• Untap target permanent.
Entwine {1} (Choose both if you pay the entwine cost.)

Skyclave Relic

Kicker {3}
Indestructible
When this artifact enters, if it was kicked, create two tapped tokens that are copies of this artifact.
{T}: Add one mana of any color.

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Micromancer

When this creature enters, you may search your library for an instant or sorcery card with mana value 1, reveal it, put it into your hand, then shuffle.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Chilling Trap

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

Sea Gate Oracle

When this creature enters, look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Sol Ring

Spark Double

You may have this creature enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Siren's Ruse

Exile target creature you control, then return that card to the battlefield under its owner's control. If a Pirate was exiled this way, draw a card.

Clockspinning

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Choose a counter on target permanent or suspended card. Remove that counter from that permanent or card or put another of those counters on it.

Cloudpost

This land enters tapped.
{T}: Add {C} for each Locus on the battlefield.

Island

Sleight of Mind

Change the text of target spell or permanent by replacing all instances of one color word with another. (For example, you may change "target black spell" to "target blue spell." This effect lasts indefinitely.)

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice this artifact: Create a 10/10 colorless Eldrazi creature token.

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Negate

Shipwreck Dowser

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Powerstone Shard

{T}: Add {C} for each artifact you control named Powerstone Shard.

Wizard's Retort

This spell costs {1} less to cast if you control a Wizard.
Counter target spell.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Cerulean Wisps

Target creature becomes blue until end of turn. Untap that creature.
Draw a card.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Cloudkin Seer

Flying
When this creature enters, draw a card.

Fleeting Distraction

Target creature gets -1/-0 until end of turn.
Draw a card.

Mechanized Production

Enchant artifact you control
At the beginning of your upkeep, create a token that's a copy of enchanted artifact. Then if you control eight or more artifacts with the same name as one another, you win the game.

Patron Wizard

Tap an untapped Wizard you control: Counter target spell unless its controller pays {1}.

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Naban, Dean of Iteration

If a Wizard you control entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Venser, Shaper Savant

Flash (You may cast this spell any time you could cast an instant.)
When Venser enters, return target spell or permanent to its owner's hand.

Familiar's Ruse

As an additional cost to cast this spell, return a creature you control to its owner's hand.
Counter target spell.

Trickbind

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Counter target activated or triggered ability. If a permanent's ability is countered this way, activated abilities of that permanent can't be activated this turn. (Mana abilities can't be targeted.)

Vesuvan Duplimancy

Whenever you cast a spell that targets only a single artifact or creature you control, create a token that's a copy of that artifact or creature, except it's not legendary.

Scourge of Fleets

When this creature enters, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Thought Vessel

Twisted Image

Switch target creature's power and toughness until end of turn.
Draw a card.

Sakashima of a Thousand Faces

You may have Sakashima enter as a copy of another creature you control, except it has Sakashima's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Cloud of Faeries

Flying
When this creature enters, untap up to two lands.
Cycling {2} ({2}, Discard this card: Draw a card.)

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, counter target spell, activated ability, or triggered ability.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Peregrine Drake

Flying
When this creature enters, untap up to five lands.

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Leap

Target creature gains flying until end of turn.
Draw a card.

Stream of Unconsciousness

Salvager of Secrets

Twiddle

You may tap or untap target artifact, creature, or land.

Mnemonic Wall

Defender
When this creature enters, you may return target instant or sorcery card from your graveyard to your hand.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Mind Games

Buyback {2}{U} (You may pay an additional {2}{U} as you cast this spell. If you do, put this card into your hand as it resolves.)
Tap target artifact, creature, or land.

Riverwise Augur

When this creature enters, draw three cards, then put two cards from your hand on top of your library in any order.

Rescue

Return target permanent you control to its owner's hand.

Mizzium Skin

Target creature you control gets +0/+1 and gains hexproof until end of turn.
Overload {1}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Arcane Signet

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

Aquitect's Will

Put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it. If you control a Merfolk, draw a card.

Shell Shield

Kicker {1} (You may pay an additional {1} as you cast this spell.)
Target creature you control gets +0/+3 until end of turn. If this spell was kicked, that creature also gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Essence Scatter

Aether Channeler

When this creature enters, choose one —
• Create a 1/1 white Bird creature token with flying.
• Return another target nonland permanent to its owner's hand.
• Draw a card.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Dive Down

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Wipe Away

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Return target permanent to its owner's hand.

Mystic Sanctuary

({T}: Add {U}.)
This land enters tapped unless you control three or more other Islands.
When this land enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.