Signs of Worse to Come

If this is the first spell cast, you may cast it
without paying it's mana cost, and you may cast
it as though it had flash.
At the beginning of each upkeep, that player
creates a 0/1 Eldrazi Scion with "Sacrifice this creature: Add {c}" if they control a Waste.
Though not dangerous on their own, the people of
Zendikar knew what the arrival of the scions meant:
a full scale invasion.