Root Sliver

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

Sidewinder Sliver

All Sliver creatures have flanking. (Whenever a creature without flanking blocks a Sliver, the blocking creature gets -1/-1 until end of turn.)

Hunter Sliver

All Sliver creatures have provoke. (Whenever a Sliver attacks, its controller may have target creature defending player controls untap and block it if able.)

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.)

Lotus Petal

{T}, Sacrifice this artifact: Add one mana of any color.

Sliver Legion

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

Plains

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Mountain

Galerider Sliver

Sliver creatures you control have flying.

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.

Megantic Sliver

Muscle Sliver

Horned Sliver

Swamp

Chromatic Lantern

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

Ancient Ziggurat

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

Striking Sliver

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

Sentinel Sliver

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

Sinew Sliver

Crystalline Sliver

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

Island

Essence Sliver

Whenever a Sliver deals damage, its controller gains that much life.

Harmonic Sliver

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

Quick Sliver

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

Cavern of Souls

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, and that spell can't be countered.

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.

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.)

Forest

Glimpse of Nature

Whenever you cast a creature spell this turn, draw a card.

Thran Quarry

At the beginning of the end step, if you control no creatures, sacrifice this land.
{T}: Add one mana of any color.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Predatory Sliver

Sliver Hivelord

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

Opaline Sliver

All Slivers have "Whenever this permanent becomes the target of a spell an opponent controls, you may draw a card."