Witherbloom’s slogan is to “get your hands dirty,” but I’d recommend washing your hands clean of drafting Witherbloom in Strixhaven Limited unless it’s wide open if you want to maximize your win rate.
Unfortunately, Witherbloom doesn’t have a clear, focused game plan that you can stick to as a recipe for success from what I’ve seen. In my opinion, the deck suffers a considerable amount from being a jack of all trades and master of none. The best synergies in the deck are the life gain synergies, but even those are a bit anemic when compared to the powerful aggression of Silverquill or the late-game inevitability of Quandrix.
I’ve had the most success with Witherbloom by focusing on raw card quality over synergy. Similar to how Lorehold is best built in imitation of Silverquill decks despite that not being its intended design, I’ve found Witherbloom works best when you build it as a Quandrix-esque deck. Instead of cards like Bury in Books and raw card advantage spells, you trade that for premium removal from black. Once you have raw card quality, if you can manage to sparingly squeeze in some of the wombo-combo cards discussed later in the article, I think you’ll have the best version of Witherbloom.