Palutena's Bow, otherwise known as the Sacred Bow of Palutena is the main weapon of choice of Pit in the Kid Icarus series. It is a standard bow given to Pit after Medusa's attack on Angel Land to help him escape his prison and stop Medusa. The bow was first named in Super Smash Bros. Brawl where it is given a larger importance and fires Palutena's Arrows.
Following Medusa's invasion of Angel Land, Pit was imprisoned in the Underworld. Simultaneously Palutena was locked up in the Palace in the Sky and in an last resort to save Angel Land she used the last of her powers to free Pit and grant him with this bow. The bow was relatively weak, but during his adventures in the first two games, Pit was given stronger arrows to use by Zeus in Sacred Chambers when he had demonstrated bravery, such as defeating lots of enemies, and proven himself worthy. The bow isn't the strongest weapon Pit can use however. In Sacred Training Chambers Zeus would put Pit to test, and by clearing the test Pit is awarded with one of three weapons, one of them being the Sacred Bow, or Long Bow as it is called in Of Myths and Monsters, which's arrows travel further.
In Super Smash Bros. Brawl the bow is given a makeover and it is revealed that it can actually split into two separate swords that can be used in hand-to-hand combat. The trophy states that it is the bow that was given to Pit following Medusa's takeover, despite its name being similar to the Sacred Bow. While the bow is the weaker one, the arrows, called Palutena's Arrow, are likely the Light Arrows, one of the Three Sacred Treasures, seeing as Pit otherwise uses standard arrows.
When Pit uses his Standard Special in Brawl he draws the bowstring and charges the Palutena's Arrow while the button is held. While charging, the direction can be changed, and the arrow can even be curved in midair after releasing the button. Compared to other characters' arrows, Palutena's Arrow moves very quickly through the air.
The bow Pit got from Palutena after the Medusa incident. As a standard bow, it's capable of firing arrows of light that can change direction. It can also be split to form two short swords--Pit holds one sword in his right hand in a standard grip and one in his left in a reverse grip. He may hold them like this so he can shift between bow and swords without losing a beat.