Release the Titans

Spend only green and colorless mana to cast
Release the Titans.
Search your library for up to three creature cards
with different names and exile them, then shuffle
your library. An opponent chooses one of them.
Cast the rest without paying their mana costs.
They can't be countered.
In trying to save Zendikar from the Eldrazi,
Nissa only damned it to their depredations.