Precipitous Drop is a common Enchantment — Aura card from Adventures in the Forgotten Realms (AFR), collector number 115. Current market price: $0.24 (foil $0.14), TCGplayer market prices via Scryfall.
Enchant creature When this Aura enters, venture into the dungeon. (Enter the first room or advance to the next room.) Enchanted creature gets -2/-2. It gets -5/-5 instead as long as you've completed a dungeon.