Stiflenought vs Sneak and Show

Sneak and Show is a combo deck racing to resolve Show and Tell or Sneak Attack into Atraxa, Grand Unifier or Emrakul, the Aeons Torn, so Force of Negation is essential as a free counter you can fire on their turn to stop the key enabler before it resolves. Consign to Memory handles their colorless spells (Lotus Petal activations aren't targetable, but it can counter Omniscience's triggered-free-cast is not relevant; it mainly answers colorless spells and triggered/activated abilities), giving you reach against their mana acceleration. Prismatic Ending is weaker here since their early permanents are rarely the thing you need to answer compared to the actual enchantments/creatures being cheated in, and Flow State is too slow against a deck that can win as early as turn two or three. Prioritize counterspell density and keep Stifle in to interrupt a Sneak Attack activation.