It's possible that, as brackets continue to increase in adoption, maybe this would be an acceptable Game Changer, though, even then, Upgraded decks don't want mass land denial around
Kain, Traitorous Dragoon Rating: 4/10 While Kain, Traitorous Dragoon is a really cool and flavorful design, it just doesnt work for me
2 foil borderless cards (either 2 rare foil borderless cards or 1 rare and 1 mythic rare foil borderless card), 2 foil rares or mythics (2 rare foil regular frame cards or 1 rare and 1 mythic rare foil regular frame card), 8 foil uncommons, 9 foil commons, and 12 full-art basic lands (2 foil and 10 non-foil)
Callous Sell-Sword Having a fling thats good against counterspells is nice, but being bad against spot removal makes it overall worse
the Coalition)
Spore Cloud: C This is a weird one since it taps the blocking creatures and prevents both attacking and blocking creatures from untapping, so you can use it to lock down two players boards, but maybe wait until after damage