Spark of Creativity

Choose target creature. Exile the top card of your library. You may have Spark of Creativity deal damage to that creature equal to the exiled card's mana value. If you don't, you may play that card until end of turn.

Eldrazi Aggressor

Devoid (This card has no color.)
Eldrazi Aggressor has haste as long as you control another colorless creature.

Frontline Rebel

Frontline Rebel attacks each combat if able.

Goblin Firestarter

Sacrifice Goblin Firestarter: It deals 1 damage to any target. Activate only during your turn, before attackers are declared.

Rapacious One

Trample
Whenever Rapacious One deals combat damage to a player, create that many 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this creature: Add {C}."