Boros Energy is a fast aggressive deck full of cheap creatures and burn. Dauthi Voidwalker is an evasive attacker that pressures their life total and exiles cards headed to their graveyard. Shadow means it can't block their creatures, so it is purely a clock. Consign to Memory counters triggered abilities, such as Ocelot Pride's end-step token trigger or Ragavan's combat-damage trigger, and the Replicate cost lets us hit more than one. Thought Scour is weak when we need to be proactive against their clock, and Persist is often too slow/clunky against a deck that kills our creatures efficiently with Galvanic Discharge and removal. Prioritize Fatal Push and Thoughtseize on their key threats (Ragavan, Ajani, Guide of Souls) before they snowball, and watch for Blood Moon which can strand our nonbasic-heavy manabase.