Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Bring to Light

Converge — Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.

Frontier Bivouac

This land enters tapped.
{T}: Add {G}, {U}, or {R}.

Return to Dust

Exile target artifact or enchantment. If you cast this spell during your main phase, you may exile up to one other target artifact or enchantment.

Profane Tutor

Suspend 2—{1}{B} (Rather than cast this card from your hand, pay {1}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search your library for a card, put that card into your hand, then shuffle.

Haunting Voyage

Choose a creature type. Return up to two creature cards of that type from your graveyard to the battlefield. If this spell was foretold, return all creature cards of that type from your graveyard to the battlefield instead.
Foretell {5}{B}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Necrotic Sliver

All Slivers have "{3}, Sacrifice this permanent: Destroy target permanent."

Sentinel Sliver

Sliver creatures you control have vigilance. (Attacking doesn't cause them to tap.)

Mountain

Plains

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Thorncaster Sliver

Sliver creatures you control have "Whenever this creature attacks, it deals 1 damage to any target."

Reflex Sliver

Wooded Bastion

{T}: Add {C}.
{G/W}, {T}: Add {G}{G}, {G}{W}, or {W}{W}.

Secluded Courtyard

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Simic Growth Chamber

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {G}{U}.

The First Sliver

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Sliver spells you cast have cascade.

Fist of Suns

You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Sinew Sliver

Counterspell

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Kindred Summons

Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.

Pillar of Origins

As this artifact enters, choose a creature type.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Harmonic Sliver

All Slivers have "When this permanent enters, destroy target artifact or enchantment."

Sliver Overlord

{3}: Search your library for a Sliver card, reveal that card, put it into your hand, then shuffle.
{3}: Gain control of target Sliver. (This effect lasts indefinitely.)

Damn

Destroy target creature. A creature destroyed this way can't be regenerated.
Overload {2}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Unclaimed Territory

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Sliver Queen

{2}: Create a 1/1 colorless Sliver creature token.

Steely Resolve

As this enchantment enters, choose a creature type.
Creatures of the chosen type have shroud. (They can't be the targets of spells or abilities.)

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

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.

Sliver Hive

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Sliver spell.
{5}, {T}: Create a 1/1 colorless Sliver creature token. Activate only if you control a Sliver.

Island

Leeching Sliver

Whenever a Sliver you control attacks, defending player loses 1 life.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Jetmir's Garden

({T}: Add {R}, {G}, or {W}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Temple of Epiphany

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {R}.

Virulent Sliver

All Sliver creatures have poisonous 1. (Whenever a Sliver deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)

Clot Sliver

All Slivers have "{2}: Regenerate this permanent."

Venom Sliver

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Fabled Passage

{T}, Sacrifice this land: 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.

Savage Lands

This land enters tapped.
{T}: Add {B}, {R}, or {G}.

Have

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Exotic Orchard

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

Command Tower

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

Wound Reflection

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Sliver Legion

All Sliver creatures get +1/+1 for each other Sliver on the battlefield.

Ziatora's Proving Ground

({T}: Add {B}, {R}, or {G}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Lavabelly Sliver

Sliver creatures you control have "When this creature enters, it deals 1 damage to target player or planeswalker and you gain 1 life."

Ward Sliver

As this creature enters, choose a color.
All Slivers have protection from the chosen color.

Despark

Exile target permanent with mana value 4 or greater.

Herald's Horn

As this artifact enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."

Forest

Syphon Sliver

Sliver creatures you control have lifelink. (Damage dealt by a Sliver creature you control also causes you to gain that much life.)

Diffusion Sliver

Whenever a Sliver creature you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.

Call to the Kindred

Enchant creature
At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

Muscle Sliver

Swamp

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Two-Headed Sliver

All Sliver creatures have menace. (They can't be blocked except by two or more creatures.)

Might Sliver

Oubliette

When this enchantment enters, target creature phases out until this enchantment leaves the battlefield. Tap that creature as it phases in this way. (Auras and Equipment phase out with it. While permanents are phased out, they're treated as though they don't exist.)

Ancient Ziggurat

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Heart Sliver

Mystic Remora

Cumulative upkeep {1} (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.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Shifting Sliver

Slivers can't be blocked except by Slivers.

Chromatic Lantern

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

Constricting Sliver

Sliver creatures you control have "When this creature enters, you may exile target creature an opponent controls until this creature leaves the battlefield."

Root Sliver

This spell can't be countered.
Sliver spells can't be countered.

Temple of Enlightenment

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {U}.

Triumphant Reckoning

Return all artifact, enchantment, and planeswalker cards from your graveyard to the battlefield.

Horizon Stone

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

Warped Landscape

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

Evolving Wilds

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

Manaweft Sliver

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

Cloud Key

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Blasphemous Act

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

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Sliver Hivelord

Sliver creatures you control have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Gruul Turf

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Winged Sliver

Reflections of Littjara

As this enchantment enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Tempered Sliver

Sliver creatures you control have "Whenever this creature deals combat damage to a player, put a +1/+1 counter on it."

Izzet Boilerworks

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Quick Sliver

Flash
Any player may cast Sliver spells as though they had flash.

Spara's Headquarters

({T}: Add {G}, {W}, or {U}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)