rewarding you for holding on to any Eldrazi Spawn or Eldrazi Scion tokens you create to make a big annihilating swing when you activate Azlask's ability. It's an interesting sub-strategy ...

They can either give a target creature +3/-3 until the end of the turn, flicker a nonland permanent, or create a 1/1 colorless Eldrazi Scion that can be sacrificed for one colorless mana.