Similarly, the Rainbow Secret Rare recolor enhances Altaria's simple color palette
2 Necron Dynasties An Eternal Evil The only mono-colored Universes Beyond deck is the Necron Dynasties, a deck with all sorts of artifact synergies and reanimator effects to ensure nothing stays dead for long
The most notable of these is Monastery Mentor, who not only has Prowess it will also spit out a token with Prowess any time you cast a non-creature spell
With so many enters-the-battlefield triggers and scary creatures in green, it's well worth being able to pull things out of your graveyard and recast them, and one of the best cards to help you do that is Eternal Witness
They all tap for one color, but if you put two colors into them and sacrifice them, you get a pretty decent ability
Even with the extra one card from the initial sorcery casting it hardly seems worth three more mana