Against the mirror-adjacent Goryo's Vengeance reanimator plan, Consign to Memory can counter Atraxa's enter-the-battlefield triggered ability, disrupting their Atraxa plan. Mystical Dispute is cheap and efficient against their heavily blue spell suite including Quantum Riddler and Force of Negation. Prismatic Ending struggles against their big graveyard-recursion threats once they resolve, and Witch Enchanter has few relevant targets in their list. Keep Thoughtseize, Solitude, and your own Ephemerate package to disrupt their hand and answer their reanimated threats.