Urza's Incubator

As Urza's Incubator enters the battlefield, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Groundshaker Sliver

Sliver creatures you control have trample. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Command Tower

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

Manaweft Sliver

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

Striking Sliver

Sliver creatures you control have first strike. (They deal combat damage before creatures without first strike.)

Reflex Sliver

Blur Sliver

Sliver creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Cryptolith Rite

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

Might Sliver

Mirari's Wake

Creatures you control get +1/+1.
Whenever you tap a land for mana, add one mana of any type that land produced.

Chromatic Lantern

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

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Ancient Ziggurat

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

Synchronous Sliver

Stomping Ground

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

Sentinel Sliver

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

Unclaimed Territory

As Unclaimed Territory enters the battlefield, 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 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.

Steelform Sliver

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

Forest

Belligerent Sliver

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

Lavabelly Sliver

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

Cavern of Souls

As Cavern of Souls enters the battlefield, 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, and that spell can't be countered.

Cleaving Sliver

Brood Sliver

Whenever a Sliver deals combat damage to a player, its controller may create a 1/1 colorless Sliver creature token.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Winged Sliver

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Harmonic Sliver

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

Descendants' Path

At the beginning of your upkeep, reveal the top card of your library. If it's a creature card that shares a creature type with a creature you control, you may cast it without paying its mana cost. If you don't cast it, put it on the bottom of your library.

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}.

Jungle Shrine

Jungle Shrine enters the battlefield tapped.
{T}: Add {R}, {G}, or {W}.

Battle Sliver

Leeching Sliver

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

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

Shifting Sliver

Slivers can't be blocked except by Slivers.

Horned Sliver

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Gemhide Sliver

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

Sliver Queen

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

Fury Sliver

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.

Thorncaster Sliver

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

Megantic Sliver

Mystic Monastery

Mystic Monastery enters the battlefield tapped.
{T}: Add {U}, {R}, or {W}.

Mountain

Opulent Palace

Opulent Palace enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.

Plains

Necrotic Sliver

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

Path of Ancestry

Path of Ancestry enters the battlefield 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.)

Galerider Sliver

Sliver creatures you control have flying.

Bonescythe Sliver

Sliver creatures you control have double strike. (They deal both first-strike and regular combat damage.)

Hibernation Sliver

All Slivers have "Pay 2 life: Return this permanent to its owner's hand."

Sandsteppe Citadel

Sandsteppe Citadel enters the battlefield tapped.
{T}: Add {W}, {B}, or {G}.

Crumbling Necropolis

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

Sliver Hivelord

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

Pulmonic Sliver

All Sliver creatures have flying.
All Slivers have "If this permanent would be put into a graveyard, you may put it on top of its owner's library instead."

Island

Telekinetic Sliver

All Slivers have "{T}: Tap target permanent."

Herald's Horn

As Herald's Horn enters the battlefield, 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.

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.)

Quick Sliver

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

Blood Crypt

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

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Tempered Sliver

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

Bonesplitter Sliver

Temple Garden

({T}: Add {G} or {W}.)
As Temple Garden enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Seaside Citadel

Seaside Citadel enters the battlefield tapped.
{T}: Add {G}, {W}, or {U}.

Steam Vents

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

Muscle Sliver

Swamp

Toxin Sliver

Whenever a Sliver deals combat damage to a creature, destroy that creature. It can't be regenerated.

Heart Sliver

Nomad Outpost

Nomad Outpost enters the battlefield tapped.
{T}: Add {R}, {W}, or {B}.

Two-Headed Sliver

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

Constricting Sliver

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

Crystalline Sliver

All Slivers have shroud. (They can't be the targets of spells or abilities.)

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Door of Destinies

As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Watcher Sliver

Sliver Legion

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

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.

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.)

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Lancer Sliver

Sliver creatures you control have first strike.

Exotic Orchard

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

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Mana Confluence

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

Sinew Sliver

Predatory Sliver

Syphon Sliver

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

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.