Even if you just have a few mana sources up after casting it you can now tap them for triple mana to essentially give you another turn
Ally cards represent people that unite for a greater cause, whether its to explore the world of Zendikar, defend against the Eldrazi, and more
The gems offer more bang for their buck and can be used to purchase a multitude of cards, generally in bigger quantities
BPhillipYork: Another unconditional sacrifice, plenty of looping you could do with this, also works well with Marionette Apprentice or Master or Disciple of the Vault
Its ban in Modern was a long time coming
Part of the reason we developed the format the way we did was to ensure that there would always be a safe haven for decks that might not necessarily perform perfectly but have something else to them, something endearing and attractive