Jund Wildfire's entire engine revolves around sacrificing artifacts like Ichor Wellspring and casting Refurbished Familiar off cheap artifact costs, so Annul can strip a key piece like Ichor Wellspring or Makeshift Munitions before it generates value. Nihil Spellbomb doesn't stop their artifact-sacrifice loops since those aren't graveyard-dependent, but it can exile their flashback cards like Eviscerator's Insight incidentally; keep expectations modest. Cut Abandon Attachments and Spell Pierce since this matchup rewards proactive interaction over card selection, and Spell Pierce's tax is easily paid by a deck with abundant mana from land ramp.