Magical twin hand axes which are praised for their sharpness
Galatine (ガラティン,Garatin?) is an item that appears Sonic and the Black Knight. It is one of the unlockable weapons in the game that can be equipped to and wielded by Sir Gawain. They are Gawain's signature magical twin swords and are one of the Sacred Swords found in the world of Camelot. They can be dual-wielded in battle where they complement the Gawain's close-quarters combat style and they are praised for their absolute sharpness. It is the second sword that Sonic collects in the Adventure Mode of the game.
Despite being regarded as swords, Galatine resembles more a pair of twin broadaxes. They each have a single silver edge with two spikes, which are attached to the side of a brown curve surface with light brown swirl patterns. The heads of Galatine themselves are attached to the hafts with metal staple which are connected to the brown upper part of the grips, which are white and have pointy golden sword pummels.
Press the B button when there is energy in the Soul Gauge.
In Sonic and the Black Knight Galatine had been in the possession of Sir Gawain for an unprecedented amount of time. It is possible, though, that Galatine might have originally been a part of the legendary sword Excalibur, but was then divided into Galatine and the other Sacred Swords when Excalibur's light was lost.
In the end, Sonic managed to best Gawain in battle, and Gawain tried to commit suicide by using one of Galatine's swords to slice his throat as he had failed his duty to King Arthur. Sonic, however, stopped Gawain's suicide attempt by taking Galatine, and then left with both blades of Gawain.
Sonic later used Galatine in conjunction with Arondight, Laevatein and Caliburn to neutralize the immortality granted by the Scabbard of Excalibur's during his final battle with King Arthur and succeeded, thus allowing Sonic to finally defeat the evil king.
When Merlina betrayed Sonic and tried to take control over the kingdom, Sonic gave Galatine back to Gawain, who used it to help the others set up a barrier to contain Merlina's power, though the barrier proved to be too weak. During Sonic's final battle with the Dark Queen, Galatine was used along with Arondight and Laevatein to help Sonic and Caliburn transform into Excalibur Sonic and Excalibur.
Real World Background
Much like the other Sacred Swords, despite Galatine being regarded as the name of Sir Gawain's sword in modern times, it was never given any real name in any surviving piece of the original Arthurian fiction. In the 15th century, Sir Thomas Malory's work, Le Morte d'Arthur named Gawain's swords as Galatine. The Winchester manuscript of Malory was given a longer version of the Roman war which contained another mention of the sword in that version of the text called "Galantine".
Other tales of Gawain, however, either do not mention any name for Gawain’s sword or instead gives Gawain the sword Caliburn/Escalibor, which Malory calls "Excalibur". One would assume that Arthur has lent him the sword, more-or-less permanently, as Gawain is still a young fighter while Arthur is mostly a staid ruler and Gawain is generally thought to be Arthur’s greatest knight, as well as Arthur’s nephew. Indeed in the work commonly called the "Vulgate Merlin" we are explicitly told that Arthur bestowed Caliburn/Excalibur on Gawain.
Galatine are sometimes referred to as the Sword(s) of the Sun, as Gawain is the Knight of the Sun.
Strangely, Sonic is only shown taking one Galatine when beating Sir Gawain, yet he has both swords when he places the swords around King Arthur during their final battle.