Preordain

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.)

Gongaga, Reactor Town

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

Shifting Sliver

Slivers can't be blocked except by Slivers.

Crystalline Sliver

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

Thran Dynamo

Negate

Guadosalam, Farplane Gateway

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

Counterspell

Dimir Guildgate

This land enters tapped.
{T}: Add {U} or {B}.

Megantic Sliver

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Harmonize

Blur Sliver

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

Sharlayan, Nation of Scholars

This land enters tapped.
{T}: Add {W} or {U}.

Blade Sliver

Azorius Guildgate

Golgari Guildgate

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

Battering Sliver

Ondu Skyruins

Ondu Inversion

Ondu Inversion // Ondu Skyruins

Vector, Imperial Capital

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

Planar Cleansing

Selesnya Guildgate

This land enters tapped.
{T}: Add {G} or {W}.

Planar Outburst

Destroy all nonland creatures.
Awaken 4—{5}{W}{W}{W} (If you cast this spell for {5}{W}{W}{W}, also put four +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Insomnia, Crown City

This land enters tapped.
{T}: Add {W} or {B}.

Forest

Bonesplitter Sliver

Gohn, Town of Ruin

Dark Ritual

Galerider Sliver

Sliver creatures you control have flying.

Boon of the Wish-Giver

Draw four cards.
Cycling {1} ({1}, Discard this card: Draw a card.)

Izzet Guildgate

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

Shadow Sliver

All Sliver creatures have shadow. (They can block or be blocked by only creatures with shadow.)

Swamp

Extinguish All Hope

Rakdos Guildgate

Mystic Monastery

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

Foresee

Sliver Hivelord

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

Windurst, Federation Center

Horned Sliver

Archivist

Plains

Dreadbore

Frontier Bivouac

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

Boros Signet

Mortify

Asphyxiate

Bedevil

Destroy target artifact, creature, or planeswalker.

Fury Sliver

Talon Sliver

Striking Sliver

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

Izzet Signet

Heart Sliver

Sol Ring

Cleaving Sliver

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.)

Two-Headed Sliver

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

Noble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {G}, {W}, or {U}.

Syphon Sliver

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

Organic Extinction

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Destroy all nonartifact creatures.

Dimir Signet

Day of Judgment

Orzhov Guildgate

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.)

Opulent Palace

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

Treno, Dark City

Sublime Exhalation

Undaunted (This spell costs {1} less to cast for each opponent.)
Destroy all creatures.

Nomad Outpost

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

Muscle Sliver

Spinneret Sliver

Back to Nature

Simic Signet

Might Sliver

Sandsteppe Citadel

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

Deliberate

Sinew Sliver

Ignoble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {B}, {R}, or {G}.

Island

Seaside Citadel

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

Pull from Tomorrow

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Gruul Guildgate

Winged Sliver

Predatory Sliver

Braingeyser

Orzhov Signet

Boros Guildgate

This land enters tapped.
{T}: Add {R} or {W}.

Mountain

Battle Sliver

Simic Guildgate

Rakdos Signet

Azorius Signet

Sentinel Sliver

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