Heal What Has Been Hurt is a three-cost song with a distinct ability to heal and draw a card, whose cost can be mitigated by exerting a three-cost character (as all Songs)
We would have had to lean heavier into an artifact build, and even play Mycosynth LatticeMycosynth Lattice, but I didn't want to go there
Nature's Rhythm This -cost sorcery will put a creature with X cost or less on the battlefield from your library, and then you can do it again for X and four green with Harmonize
Astral Slide (S, Block?) The newest white power card on the block, Astral Slide so far stands out as the frontrunner in the "best Onslaught card" contest
I was glad eldrazi got some love, but I have not been impressed with this what looks like a big mana commander
Variables: N is about 3.5 from my observations, and that already accounts for the fact you pick some Mythics, so no further adjustment needed there