Swamp

Dust Stalker

Devoid (This card has no color.)
Haste
At the beginning of each end step, if you control no other colorless creatures, return Dust Stalker to its owner's hand.

Crumbling Vestige

Crumbling Vestige enters tapped.
When Crumbling Vestige enters, add one mana of any color.
{T}: Add {C}. ({C} represents colorless mana.)

Mountain

Reaver Drone

Devoid (This card has no color.)
At the beginning of your upkeep, you lose 1 life unless you control another colorless creature.

Outnumber

Outnumber deals damage to target creature equal to the number of creatures you control.

Unnatural Endurance

Devoid (This card has no color.)
Target creature gets +2/+0 until end of turn. Regenerate it.

Bearer of Silence

Devoid (This card has no color.)
When you cast this spell, you may pay {1}{C}. If you do, target opponent sacrifices a creature. ({C} represents colorless mana.)
Flying
Bearer of Silence can't block.

Flayer Drone

Devoid (This card has no color.)
First strike
Whenever another colorless creature you control enters, target opponent loses 1 life.

Vile Aggregate

Devoid (This card has no color.)
Vile Aggregate's power is equal to the number of colorless creatures you control.
Trample
Ingest (Whenever this creature deals combat damage to a player, that player exiles the top card of their library.)

Transgress the Mind

Devoid (This card has no color.)
Target player reveals their hand. You choose a card from it with mana value 3 or greater and exile that card.

Forerunner of Slaughter

Devoid (This card has no color.)
{1}: Target colorless creature gains haste until end of turn.

Corrupted Crossroads

{T}: Add {C}. ({C} represents colorless mana.)
{T}, Pay 1 life: Add one mana of any color. Spend this mana only to cast a spell with devoid.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Eldrazi Obligator

Devoid (This card has no color.)
When you cast this spell, you may pay {1}{C}. If you do, gain control of target creature until end of turn, untap that creature, and it gains haste until end of turn. ({C} represents colorless mana.)
Haste