Interestingly, youll find a ton of mono-green decks that run a copy or two of Elesh Norn, Mother of Machines, which stops a lot of the affinity and energy decks gameplans
This required a change to the rules to allow cards that are on an Adventure be played from exile using its primary characteristics (that is, the non-Adventure part of the card), rather than allowing the non-Adventure spell to be cast
What Ravnica did for its two-color guilds, Shards of Alara has done for its three-color shards
The simple ability to cast a bunch of free spells is something thats worth building around, and its worth putting Abaddon into other decks too
Spark Doubles additional counter opens the door to various synergies with proliferate and other counter shenanigans
Era of Innovation is an auto-include in Energy decks