Ruthless Regiment - Boros
Arcane Maelstrom - Izzet
Symbiotic Swarm - Golgari
Timeless Wisdom - Azorius?
Enhanced Evolution - Simic
Those are my guesses. I'm excited for Golgari and Simic particularly (if they are what I
predict). I've been considering taking apart my Kumena deck, and I have lots of good duals, counterspells, etc. that I can add to power up it if I am interested.