Musica Sword (ムジカの剣 Mujika no Ken) is an extremely expensive weapon formerly wielded by Bis (an unnamed Grimoire Heart Mage in the anime) until it was stolen by Panther Lily, who subsequently took it as his own.
The Musica Sword possesses a long, curved blade, which is light-colored on the edges and dark on the rest, and which protrudes on both sides near its top, and has a large, light symbol carved near its hilt, representing a musical note. The design of the handguard is intricate and decorated: it extends over the blade itself, with a shiny decoration similar to a large curved claw placed horizontally towards the weapon's cutting edge, where a large, shiny curved part seemingly acting as a rough front protection of sort is placed. On the other side, the "claw" ends in a wing-like ornament, consisting of three large metal feathers. The part connecting the hilt to the blade curves towards the latter, and is divided into a series of rectangular forms by a series on line on it; the blade’s back edge is also shown slightly emerging from under such part, protruding downwards. The hilt is long and covered in leather stripes, and it ends into a large pommel yet again similar to a claw pointing towards the blade, or maybe a stylized bird's head, ending in a wing-like ornament, with its three feathers pointing downwards, which is smaller and less-detailed than the one on the blade.
The sword has the ability to change in size. Panther Lily claimed that it reminded him very much of his Bustermarm. Such characteristic allows him to carry the weapon around in both his original and reduced form, being capable of changing its size at will to adapt it to the situation. He has been shown carrying the weapon on his back, with the hilt visible from behind his right shoulder, held up by a stripe crossing his chest diagonally.
- In Hiro Mashima's previous work, Rave Master, there was a character named Musica, who was a blacksmith capable of creating weapons with magical properties. The musical note carved onto the sword's blade is also the same which Musica used to put on the weapons he created.
- In the manga, the original wielder of the sword before Panther Lily takes it is the Demon Card member Bis from Rave Master.
- Musica is the Catalan, Spanish, Portuguese and Italian word for "music".