UBR is a durdly control-combo deck leaning on Indomitable Creativity and big top-end like Atraxa, Grand Unifier and Valgavoth, Terror Eater, so Spell Pierce punishes their noncreature spells (Make Disappear, Fable of the Mirror-Breaker, Indomitable Creativity) while they're tapped out setting up. Redcap Melee is your best removal for anything Indomitable Creativity or Fable of the Mirror-Breaker generates. Abandon Attachments helps you dig and refill after they try to grind with Deduce. Screaming Nemesis is risky since it dies easily to their removal suite before it matters, and Monstrous Rage/Boomerang Basics are too low-impact against a deck that wants to go over the top. Keep pressure high and closing speed matters since they can out-grind you late.