Eye of Ugin

Colorless Eldrazi spells you cast cost {2} less to cast.
{7}, {T}: Search your library for a colorless creature card, reveal it, put it into your hand, then shuffle.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Eldrazi Temple

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless Eldrazi spells or activate abilities of colorless Eldrazi.

Manifold Key

{1}, {T}: Untap another target artifact.
{3}, {T}: Target creature can't be blocked this turn.

Reliquary Tower

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

Darksteel Citadel

Kozilek, Butcher of Truth

When you cast this spell, draw four cards.
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Kozilek, Butcher of Truth is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

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}.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Ulamog, the Defiler

When you cast this spell, target opponent exiles the top half of their library, rounded up.
Ward—Sacrifice two permanents.
Ulamog, the Defiler enters with a number of +1/+1 counters on it equal to the greatest mana value among cards in exile.
Ulamog has annihilator X, where X is the number of +1/+1 counters on it.

Not of This World

Counter target spell or ability that targets a permanent you control.
This spell costs {7} less to cast if it targets a spell or ability that targets a creature you control with power 7 or greater.

Spawnbed Protector

At the beginning of your end step, return up to one target Eldrazi creature card from your graveyard to your hand. Create two 1/1 colorless Eldrazi Scion creature tokens with "Sacrifice this creature: Add {C}."

Ugin's Mastery

Whenever you cast a colorless creature spell, manifest the top card of your library. (Put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Whenever you attack with creatures with total power 6 or greater, you may turn a face-down creature you control face up.

Kozilek, the Great Distortion

When you cast this spell, if you have fewer than seven cards in hand, draw cards equal to the difference.
Menace
Discard a card with mana value X: Counter target spell with mana value X.

Eldrazi Conscription

Enchant creature
Enchanted creature gets +10/+10 and has trample and annihilator 2. (Whenever it attacks, defending player sacrifices two permanents of their choice.)

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Sol Ring

Tomb of the Spirit Dragon

{T}: Add {C}.
{2}, {T}: You gain 1 life for each colorless creature you control.

Emrakul, the Promised End

This spell costs {1} less to cast for each card type among cards in your graveyard.
When you cast this spell, you gain control of target opponent during that player's next turn. After that turn, that player takes an extra turn.
Flying, trample, protection from instants

Ugin, the Spirit Dragon

+2: Ugin, the Spirit Dragon deals 3 damage to any target.
−X: Exile each permanent with mana value X or less that's one or more colors.
−10: You gain 7 life, draw seven cards, then put up to seven permanent cards from your hand onto the battlefield.

It That Betrays

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control.

Mystic Forge

You may look at the top card of your library any time.
You may cast artifact spells and colorless spells from the top of your library.
{T}, Pay 1 life: Exile the top card of your library.

Perilous Vault

{5}, {T}, Exile Perilous Vault: Exile all nonland permanents.

Kozilek's Command

Choose two —
• Target player creates X 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this creature: Add {C}."
• Target player scries X, then draws a card.
• Exile target creature with mana value X or less.
• Exile up to X target cards from graveyards.

Ulamog, the Ceaseless Hunger

When you cast this spell, exile two target permanents.
Indestructible
Whenever Ulamog, the Ceaseless Hunger attacks, defending player exiles the top twenty cards of their library.

Titan's Presence

As an additional cost to cast this spell, reveal a colorless creature card from your hand.
Exile target creature if its power is less than or equal to the revealed card's power.

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Kozilek, the Broken Reality

When you cast this spell, up to two target players each manifest two cards from their hands. For each card manifested this way, you draw a card. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Other colorless creatures you control get +3/+2.

Scavenger Grounds

{T}: Add {C}.
{2}, {T}, Sacrifice a Desert: Exile all graveyards.

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Thran Dynamo

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Flayer of Loyalties

When you cast this spell, gain control of target creature until end of turn. Untap that creature. Until end of turn, it has base power and toughness 10/10 and gains trample, annihilator 2, and haste.
Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Trample

Calamity of the Titans

As an additional cost to cast this spell, reveal a colorless creature card from your hand.
Exile each creature and planeswalker with mana value less than the revealed card's mana value.

Void Winnower

Your opponents can't cast spells with even mana values. (Zero is even.)
Your opponents can't block with creatures with even mana values.

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Grim Monolith

Grim Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap Grim Monolith.

Mana Vault

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault.
At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Ugin's Labyrinth

Imprint — When Ugin's Labyrinth enters, you may exile a colorless card with mana value 7 or greater from your hand.
{T}: Add {C}. If a card is exiled with Ugin's Labyrinth, add {C}{C} instead.
{T}: Return the exiled card to its owner's hand.

Conduit of Ruin

When you cast this spell, you may search your library for a colorless creature card with mana value 7 or greater, reveal it, then shuffle and put that card on top.
The first creature spell you cast each turn costs {2} less to cast.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Emrakul, the World Anew

When you cast this spell, gain control of all creatures target player controls.
Flying, protection from spells and from permanents that were cast this turn
When Emrakul, the World Anew leaves the battlefield, sacrifice all creatures you control.
Madness—Pay six {C}.

Ulamog, the Infinite Gyre

When you cast this spell, destroy target permanent.
Indestructible
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Ulamog, the Infinite Gyre is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Skittering Invasion

Create five 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this creature: Add {C}."

Karn Liberated

+4: Target player exiles a card from their hand.
−3: Exile target permanent.
−14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

Echoes of Eternity

If a triggered ability of a colorless spell you control or another colorless permanent you control triggers, that ability triggers an additional time.
Whenever you cast a colorless spell, copy it. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Forsaken Monument

Colorless creatures you control get +2/+2.
Whenever you tap a permanent for {C}, add an additional {C}.
Whenever you cast a colorless spell, you gain 2 life.