Counterspell

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Exotic Orchard

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

Mountain

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Island

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Endling

{B}: Endling gains menace until end of turn.
{B}: Endling gains deathtouch until end of turn.
{B}: Endling gains undying until end of turn. (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
{1}: Endling gets +1/-1 or -1/+1 until end of turn.

Tree of Perdition

Defender
{T}: Exchange target opponent's life total with Tree of Perdition's toughness.

Sol Ring

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Jace's Archivist

{U}, {T}: Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Blood Crypt

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

Swamp

Izzet Signet

Mairsil, the Pretender

When Mairsil, the Pretender enters, you may exile an artifact or creature card from your hand or graveyard and put a cage counter on it.
Mairsil, the Pretender has all activated abilities of all cards you own in exile with cage counters on them. You may activate each of those abilities only once each turn.

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Fellwar Stone

Soliton

Morphling

{U}: Untap Morphling.
{U}: Morphling gains flying until end of turn.
{U}: Morphling gains shroud until end of turn. (It can't be the target of spells or abilities.)
{1}: Morphling gets +1/-1 until end of turn.
{1}: Morphling gets -1/+1 until end of turn.

Pendant of Prosperity

Pendant of Prosperity enters under the control of an opponent of your choice.
{2}, {T}: Draw a card, then you may put a land card from your hand onto the battlefield. Pendant of Prosperity's owner draws a card, then that player may put a land card from their hand onto the battlefield.

Displace

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

Dimir Signet

Pestilent Souleater

{B/P}: Pestilent Souleater gains infect until end of turn. ({B/P} can be paid with either {B} or 2 life. A creature with infect deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Vantress Visions

Copy target activated or triggered ability you control. You may choose new targets for the copy.

Virtue of Knowledge

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

Virtue of Knowledge // Vantress Visions

Horseshoe Crab

Quicksilver Elemental

{U}: Quicksilver Elemental gains all activated abilities of target creature until end of turn. (If any of the abilities use that creature's name, use this creature's name instead.)
You may spend blue mana as though it were mana of any color to pay the activation costs of Quicksilver Elemental's abilities.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Talisman of Creativity

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

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

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.

Arcane Signet

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

Asmodeus the Archfiend

Binding Contract — If you would draw a card, exile the top card of your library face down instead.
{B}{B}{B}: Draw seven cards.
{B}: Return all cards exiled with Asmodeus the Archfiend to their owner's hand and you lose that much life.

Aetherling

{U}: Exile Aetherling. Return it to the battlefield under its owner's control at the beginning of the next end step.
{U}: Aetherling can't be blocked this turn.
{1}: Aetherling gets +1/-1 until end of turn.
{1}: Aetherling gets -1/+1 until end of turn.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

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.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

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.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Argent Sphinx

Flying
Metalcraft — {U}: Exile Argent Sphinx. Return it to the battlefield under your control at the beginning of the next end step. Activate only if you control three or more artifacts.

Torchling

{R}: Untap Torchling.
{R}: Target creature blocks Torchling this turn if able.
{R}: Change the target of target spell that targets only Torchling.
{1}: Torchling gets +1/-1 until end of turn.
{1}: Torchling gets -1/+1 until end of turn.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

Amaranthine Wall

Defender
{2}: Amaranthine Wall gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Hateflayer

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{2}{R}, {Q}: Hateflayer deals damage equal to its power to any target. ({Q} is the untap symbol.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Pack Rat

Pack Rat's power and toughness are each equal to the number of Rats you control.
{2}{B}, Discard a card: Create a token that's a copy of Pack Rat.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Steam Vents

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

Training Center

Training Center enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Command Tower

Training Grounds

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.

Blighted Bat

Flying
{1}: Blighted Bat gains haste until end of turn.

Thrill of Possibility

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

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Crumbling Necropolis

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

Candlekeep Sage

Commander creatures you own have "When this creature enters or leaves the battlefield, draw a card."

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Relic of Sauron

{T}: Add two mana in any combination of {U}, {B}, and/or {R}.
{3}, {T}: Draw two cards, then discard a card.

Panharmonicon

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

Planar Incision

Exile target artifact or creature, then return it to the battlefield under its owner's control with a +1/+1 counter on it.

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.