Shirufe no ken
The Sylph Sword (シルフェの剣 Shirufe no ken?) or Wind Sword is one of the magical items bestowed by Flora and Schierke to Guts and his team to help Schierke in her fight against the trolls raiding Enoch Village, along with Casca and Farnese's Silver Surcoats, Farnese's Silver Dagger, Serpico's Sylph Cloak, Isidro's Salamander Dagger and the refused Axe of the Gnomes. It is wielded by Serpico.
The Sylph Sword resembles a feathery duster, as it is composed of very large feathers tied to a carved branch. However, the feathers originate from a great eagle that makes its nest on the highest perch in the magical forest in which Flora resides, and the branch/grip is carved from that same tree. Such elements allow the magical might of the Sylph, ancient elemental spirits of the wind from whom the elves descend, to flow throughout the sword. They can be seen along the sword's surface by those that are attuned to the Astral Plane.
The Sylph Sword is able to strike at a far greater distance than the length of its "blade", essentially allowing its user, should they be compatible with the Sylphs in the sword, to launch razor air currents and cut apart enemies from a distance. In the hands of a skilled fencer it can strike precisely enough to cut a candle without blowing off its fire.
Serpico, a skilled fencer in his own right, has learned how to push small items and liquids away with the elemental winds of his sword, and how to enhance his striking powers with the elemental magic.