Four Knocks is a rare Enchantment card from Doctor Who (WHO), collector number 20. Current market price: $1.06 (foil $1.07), TCGplayer market prices via Scryfall.
Vanishing 4 (This enchantment enters with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.) At the beginning of your first main phase, draw a card.