Mana Echoes

Whenever a creature enters, you may add an amount of {C} equal to the number of creatures you control that share a creature type with it.

Forest

Striking Sliver

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

Arcane Signet

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

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Utter End

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Mana Reflection

If you tap a permanent for mana, it produces twice as much of that mana instead.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Blur Sliver

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

Breeding Pool

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

Temple Garden

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

Sliver Queen

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

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Syphon Sliver

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

Plains

Sentinel Sliver

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

Skyshroud Claim

Search your library for up to two Forest 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.

Island

Horned Sliver

Homing Sliver

Each Sliver card in each player's hand has slivercycling {3}.
Slivercycling {3} ({3}, Discard this card: Search your library for a Sliver card, reveal it, put it into your hand, then shuffle.)

Stomping Ground

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

Zendikar Resurgent

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)
Whenever you cast a creature spell, draw a card.

Evolving Wilds

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

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Hallowed Fountain

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

Swamp

Reflections of Littjara

As Reflections of Littjara 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.)

Cavern of Souls

As Cavern of Souls 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.

Sol Ring

Overgrown Tomb

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

Sacred Foundry

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

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.)

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.

Pillar of Origins

As Pillar of Origins 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.

Mountain

Command Tower

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.")

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.

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.

Blood Crypt

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

Unclaimed Territory

As Unclaimed Territory 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.

Crypt Sliver

All Slivers have "{T}: Regenerate target Sliver."

Path of Ancestry

Path of Ancestry 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.)

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

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.)

Manaweft Sliver

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

Chromatic Lantern

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

Godless Shrine

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

Steam Vents

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

Shared Summons

Search your library for up to two creature cards with different names, reveal them, put them into your hand, then shuffle.

Distant Melody

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

Fellwar Stone

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

Crystalline Sliver

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

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap Forbidden Orchard for mana, target opponent creates a 1/1 colorless Spirit creature token.

Farseek

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

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."

Negate

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Belligerent Sliver

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

Exotic Orchard

Root Sliver

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

Ancient Ziggurat

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

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.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Galerider Sliver

Sliver creatures you control have flying.

Swords to Plowshares

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

Shifting Sliver

Slivers can't be blocked except by Slivers.

Counterspell

Terramorphic Expanse

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

Sliver Hivelord

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

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

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.)

Carpet of Flowers

At the beginning of each of your main phases, if you haven't added mana with this ability this turn, you may add X mana of any one color, where X is the number of Islands target opponent controls.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Watery Grave

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

Sliver Legion

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

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Harmonic Sliver

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

Lightning Greaves

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

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

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.)