Looks great, but Nettlecyst is going to be just fine most of the time
The loser of that subgame loses half of their life once the main game resumes
Most casual players are willing to trade a couple of exiled cards from their library to add another land to their fat stack, and you net cards quite often
Since the card is currently only being played in just one modern deck, I personally had it in the third spot behind the best blue reactive spells in the format, Counterspell and Force of Negation, but I can see the number one spot going to the best and most efficient threat the color has to offer
Daybound (If a player casts no spells during their own turn, it becomes night next turn.) Wildsong Howler Color Indicator: Green Creature Werewolf Whenever this creature enters or transforms into Wildsong Howler, look at the top six cards of your library
Tribal Flames Non-domain decks need not apply