One Does Not is a common Enchantment — Aura card from Unknown Event (UNK), collector number CU12a. Current market price: $15.00, TCGplayer market prices via Scryfall.
Enchant creature Enchanted creature does not simply untap during its controller's untap step. Enchanted creature has nonbasic landwalk. (It can't simply be blocked as long as defending player controls a nonbasic land.)