The Wisp in a Bottle is a pet-summoning item. When used, it will act similarly to a Fairy Bell and the Shadow Orb (Spell). It will summon a wisp that, unlike the others, will follow the player's movement inputs. It will go left if the player presses Left, and so on. This can prove to be a very useful way of locating caves and ores as it passes through walls; if the player presses down, the wisp will go down, but their character will not move. The wisp does not have a duration to it. It cannot be active at the same time as the Fairy Bell or a Shadow Orb. The wisp functions like a pet that follows you around.