Rakdos Madness Burn wants to race with cheap creatures like Voldaren Epicure and Kitchen Imp plus direct burn such as Lightning Bolt and Fiery Temper, so Curfew buys a full turn against their aggression by bouncing their best threat while your own creatures are minimal targets. Tormod's Crypt strips their graveyard to shut off Faithless Looting flashback and Deep Analysis-style recursion, though it does nothing against madness discards since those cards are cast from exile, not the graveyard. Flaring Pain is largely a sideboard trick against their own burn plan and only marginally useful, brought in as a low-cost swap. Murmuring Mystic is too slow and its 1/5 body doesn't block Kitchen Imp's flying haste, so it comes out for more proactive answers, and Spell Pierce is weak since this opponent runs few countermagic-relevant spells to punish. Prioritize Lightning Bolt, Skred, and Counterspell to control their board and protect your life total against a deck built to burn you out quickly.