I thought of this when I got up this morning and I couldn’t resist the pun of the title. However, the item is not punny. I just couldn’t bring myself to go that far with it.
The One Wing is a single gossamer faerie wing (similar to a the wing of a dragonfly) that will immediately mount on the back of the person that holds there for a moment (takes a single round/action to apply the wing).
The wearer of the One Wing can see all faerie creatures, even those that are ethereal, astral or invisible. In addition to this, the wearer can cross over into the plane of the fae (whatever that may be depending on game system) at will. Even though the One Wing allows entrance into the fae realms, it does not allow for immediate transport back into the mortal realms. The only way back to the prime material plane is through “normal” means, or other magical methods.
The One Wing does allow for flight, but because it is a single wing, when the wearer is flying a loud buzzing noise emanates from the PC which will attract nearby monsters, especially the fae. When the fae realize what the wearer has on his back, they will immediately attack and attempt to reclaim their relic. The One Wing is a vile creation to the fae, and they wish to destroy it and give it a proper burial.
The only way to destroy the One Wing is to soak it in holy water mixed with three drops of blood from a faerie warrior. Once the One Wing is thoroughly soaked, it must be burned in a bonfire created from dried pine needles. If any other form of combustible material is used in the fire, the One Wing will survive the conflagration.