While there are solid cards like Cut Your Losses for Bruvac mill or Hypnotic Grifter as a mana outlet in a self-mill deck, theyre a little niche and otherwise not going to add too much to your collection
Selesnya Combo Finishes cEDH Sythis decks tend to rely on stax and slowdown pieces to extend the game to find combo wincons, which are things like Sanctum Weaver plus Gauntlets of Light, Solemnity plus Nine Lives, a variety of Devoted Druid mana combos, or all the stuff in the Scurry Oak and Heliod, Sun-Crowned space
Proliferate only works on counters
These have four pieces of information: The attack name
You have some tools for that, like the goad mechanic, or an aura like Vow of Duty
And thus Innistrad: Crimson Vow will focus heavily on vampires and the increasing humans joining the fight to stop the endless night