Unlock a random Shadow's Eve recipe you don't already have unlocked.
— Item Tooltip
Shadow's Eve are Holiday Recipes that can be obtained during the Shadow's Eve Event. Shadow's Eve's can only be obtained commonly through Nightmare, Spookytime, and Haunted Mystery Boxes. They are one-time use items, and will always teach the player a Shadow's Eve recipe they don't already know. Players who know all recipes will be unable to use the Shadow's Eve Recipes, but can deconstruct them for Blank Scrolls.
Shadow's Eve Recipes
Like most recipes, Shadow's Eve Recipes will unlock a recipe that the player has not already unlocked from the respective biome it was obtained from. There are a total of 9 Shadow's Eve Recipes and can be created at the Shadowy Station in the Hub.