Izzet Prowess is full of 1-2 toughness creatures like Dragon's Rage Channeler, Monastery Swiftspear, and Slickshot Show-Off, so Brotherhood's End sweeps them for 3 damage before they get too big. Untimely Malfunction's clause letting one or two creatures not block is mostly irrelevant here, but its artifact destruction mode hits Cori-Steel Cutter, a key piece of their gameplan. This matchup is a pure race, so Artist's Talent and Valakut Awakening come out for proactive, board-impacting cards. Keep combo density high since our clock is typically faster than theirs if we survive their early creatures.