There are some interesting options to consider with playing Into the North! A lot of what green has to offer is not worth the shift, but the package of Into the North and Growth Spiral as 4 of's is very intriguing, especially in conjunction with Marit Lage's Slumber. We could be pumping out these 20'20's way ahead of schedule, and that's intriguing. So making a dedicated slumber deck seems like the positive shift. There is a lot of other cards to consider, but these are the ones that merit considering green. Additionally Yasharn/Primal Command is intriguing, and Search for glory grabs this card as well! Speaking of search for glory, adding green means I get to reconsider Search for glory packages, which is a must. All of this is well and good, but I think we are talking about a 25% rebuild of the deck, so likely needs to be stripped and then built from the ground up rather straight swaps.