Sultai Aluren wants to resolve Show and Tell into Atraxa, or land Aluren and chain cheap creatures like Acererak. Consign to Memory counters triggered abilities, such as Atraxa's enters trigger and Acererak's triggers, and it also counters colorless spells like Lotus Petal, so it is a flexible answer to their key plays. Fragmentize can destroy Aluren (mana value 4) and also hits Lotus Petal, so it takes out their engine. Pithing Needle is left out, since Aluren has no activated ability to shut off and their relevant activated abilities (fetchlands) are too spread out for a single name to matter. Relic of Progenitus has little to interact with here since their plan isn't graveyard-dependent, and Shuko doesn't help race a deck that is also combo-oriented. Prioritize resolving our own combo quickly since this matchup is largely a race between two glass-cannon strategies.