Azlask, the Swelling Scourge

Whenever Azlask, the Swelling Scourge or another colorless creature you control dies, you get an experience counter.
{W}{U}{B}{R}{G}: Creatures you control get +X/+X until end of turn, where X is the number of experience counters you have. Scions and Spawns you control gain indestructible and annihilator 1 until end of turn.

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.

Null Elemental Blast

Choose one —
• Counter target multicolored spell.
• Destroy target multicolored permanent.

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.

It That Betrays

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

Brood Monitor

Devoid (This card has no color.)
When Brood Monitor enters the battlefield, create three 1/1 colorless Eldrazi Scion creature tokens. They have "Sacrifice this creature: Add {C}."

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 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 the battlefield 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.

Spawnsire of Ulamog

Annihilator 1 (Whenever this creature attacks, defending player sacrifices a permanent.)
{4}: Create two 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this creature: Add {C}."
{20}: Cast any number of Eldrazi spells from among cards you own outside the game without paying their mana costs.

Awakening Zone

At the beginning of your upkeep, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Kozilek, Butcher of Truth

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

Ulalek, Fused Atrocity

Devoid (This card has no color.)
Whenever you cast an Eldrazi spell, you may pay {C}{C}. If you do, copy all spells you control, then copy all other activated and triggered abilities you control. You may choose new targets for the copies. (Mana abilities can't be copied.)

Emrakul's Messenger

Devoid (This card has no color.)
Flying
Whenever you draw your second card each turn, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."

Eldrazi Displacer

Devoid (This card has no color.)
{2}{C}: Exile another target creature, then return it to the battlefield tapped under its owner's control. ({C} represents colorless mana.)

Ugin's Labyrinth

Imprint — When Ugin's Labyrinth enters the battlefield, 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.

Path of Annihilation

Devoid (This card has no color.)
When Path of Annihilation enters the battlefield, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this creature: Add {C}."
Eldrazi you control have "{T}: Add one mana of any color."
Whenever you cast a creature spell with mana value 7 or greater, you gain 4 life.

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.

Drowned Jungle

Drowned Jungle enters the battlefield tapped.
{T}: Add {G} or {U}.

Drowner of Truth

Devoid (This card has no color.)
When you cast this spell, if {C} was spent to cast it, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this creature: Add {C}."

Drowner of Truth // Drowned Jungle

It That Heralds the End

Colorless spells you cast with mana value 7 or greater cost {1} less to cast.
Other colorless creatures you control get +1/+1.

Kozilek's Unsealing

Devoid (This card has no color.)
Whenever you cast a creature spell with mana value 4, 5, or 6, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this creature: Add {C}."
Whenever you cast a creature spell with mana value 7 or greater, draw three cards.

Artisan of Kozilek

When you cast this spell, you may return target creature card from your graveyard to the battlefield.
Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)

Basking Broodscale

Devoid (This card has no color.)
{1}{G}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on Basking Broodscale, you may create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."

From Beyond

Devoid (This card has no color.)
At the beginning of your upkeep, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."
{1}{G}, Sacrifice From Beyond: Search your library for an Eldrazi card, reveal it, put it into your hand, then shuffle.

Zhulodok, Void Gorger

Colorless spells you cast from your hand with mana value 7 or greater have "Cascade, cascade." (When you cast one, 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. Then do it again.)

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.

Ulamog, the Infinite Gyre

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

Idol of False Gods

{1}{C}, {T}: Create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."
Whenever another Eldrazi you control dies, put a +1/+1 counter on Idol of False Gods.
As long as Idol of False Gods has eight or more +1/+1 counters on it, it's a 0/0 creature in addition to its other types and it has annihilator 2.

Catacomb Sifter

Devoid (This card has no color.)
When Catacomb Sifter enters the battlefield, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."
Whenever another creature you control dies, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.