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.

Cinder Barrens

Cinder Barrens enters tapped.
{T}: Add {B} or {R}.

Sky Scourer

Devoid (This card has no color.)
Flying
Whenever you cast a colorless spell, Sky Scourer gets +1/+0 until end of turn.

Swarm Surge

Devoid (This card has no color.)
Creatures you control get +2/+0 until end of turn. Colorless creatures you control also gain first strike until end of turn.

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.

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.

Forerunner of Slaughter

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

Reaver Drone

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

Swamp

Complete Disregard

Devoid (This card has no color.)
Exile target creature with power 3 or less.

Ghostfire Blade

Equipped creature gets +2/+2.
Equip {3}
Ghostfire Blade's equip ability costs {2} less to activate if it targets a colorless creature.

Flayer Drone

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

Visions of Brutality

Devoid (This card has no color.)
Enchant creature
Enchanted creature can't block.
Whenever enchanted creature deals damage, its controller loses that much life.