Familiars is a combo-control deck that assembles Sunscape Familiar with Azorius Chancery and Ghostly Flicker loops to generate infinite mana and draw, often winning through Mulldrifter or Murmuring Mystic tokens. Annul is your premier answer, hitting Sunscape Familiar, Archaeomancer, Azorius Chancery, and God-Pharaoh's Faithful — prioritize countering the Familiar above all else since it enables their mana engine. Counterspell and Snuff Out are your other key tools; use Snuff Out liberally on Archaeomancer and Sea Gate Oracle to disrupt the loop even without mana. Your threats in Tolarian Terror and Sneaky Snacker apply fast clock pressure that forces them to go off quickly rather than on their own terms. Deep Analysis and Murmuring Mystic come out because the game will be decided early on tempo, and Spell Pierce is weaker than Annul here since their key pieces are artifacts and creatures.