Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Tajuru Pathwarden

Ruin Processor

When you cast this spell, you may put a card an opponent owns from exile into that player's graveyard. If you do, you gain 5 life.

Mind Raker

Devoid (This card has no color.)
When Mind Raker enters, you may put a card an opponent owns from exile into that player's graveyard. If you do, each opponent discards a card.

Eyeless Watcher

Devoid (This card has no color.)
When Eyeless Watcher enters, create two 1/1 colorless Eldrazi Scion creature tokens. They have "Sacrifice this creature: Add {C}."

Ruin in Their Wake

Devoid (This card has no color.)
Search your library for a basic land card and reveal it. You may put that card onto the battlefield tapped if you control a land named Wastes. Otherwise, put that card into your hand. Then shuffle.

Culling Drone

Devoid (This card has no color.)
Ingest (Whenever this creature deals combat damage to a player, that player exiles the top card of their library.)

Breaker of Armies

All creatures able to block Breaker of Armies do so.

Swamp

Tar Snare

Target creature gets -3/-2 until end of turn.

Unnatural Aggression

Devoid (This card has no color.)
Target creature you control fights target creature an opponent controls. If the creature an opponent controls would die this turn, exile it instead.

Matter Reshaper

({C} represents colorless mana.)
When Matter Reshaper dies, reveal the top card of your library. You may put that card onto the battlefield if it's a permanent card with mana value 3 or less. Otherwise, put that card into your hand.

Oblivion Strike

Devoid (This card has no color.)
Exile target creature.

Thought-Knot Seer

({C} represents colorless mana.)
When Thought-Knot Seer enters, target opponent reveals their hand. You choose a nonland card from it and exile that card.
When Thought-Knot Seer leaves the battlefield, target opponent draws a card.

Forest

Spatial Contortion

({C} represents colorless mana.)
Target creature gets +3/-3 until end of turn.

Island

Dominator Drone

Devoid (This card has no color.)
Ingest (Whenever this creature deals combat damage to a player, that player exiles the top card of their library.)
When Dominator Drone enters, if you control another colorless creature, each opponent loses 2 life.

Submerged Boneyard

Submerged Boneyard enters tapped.
{T}: Add {U} or {B}.

Slaughter Drone

Devoid (This card has no color.)
{C}: Slaughter Drone gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it. {C} represents colorless mana.)

Kozilek's Translator

Devoid (This card has no color.)
Pay 1 life: Add {C}. Activate only once each turn. ({C} represents colorless mana.)

Saddleback Lagac

When Saddleback Lagac enters, support 2. (Put a +1/+1 counter on each of up to two other target creatures.)

Deceiver of Form

({C} represents colorless mana.)
At the beginning of combat on your turn, reveal the top card of your library. If a creature card is revealed this way, you may have creatures you control other than Deceiver of Form become copies of that card until end of turn. You may put that card on the bottom of your library.

Lifespring Druid

Mortuary Mire

Mortuary Mire enters tapped.
When Mortuary Mire enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Coastal Discovery

Draw two cards.
Awaken 4—{5}{U} (If you cast this spell for {5}{U}, 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.)

Sanctum of Ugin

{T}: Add {C}.
Whenever you cast a colorless spell with mana value 7 or greater, you may sacrifice Sanctum of Ugin. If you do, search your library for a colorless creature card, reveal it, put it into your hand, then shuffle.

Sweep Away

Return target creature to its owner's hand. If that creature is attacking, you may put it on top of its owner's library instead.

Scion Summoner

Devoid (This card has no color.)
When Scion Summoner enters, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}." ({C} represents colorless mana.)