The Master Blades are a type of Master Weapon, and as such, are legendary, one of a kind swords. By those who know of their existence, they are considered the most powerful swords in the world. Nobody knows who made them or where they came from.
Aside from being weapons of unimaginable quality and strength, they are legendary because of the extrodinary feats they can do.
A mighty sword that is larger than a fully grown man. It is said that this blade was once the knife of a giant.
One of the few of the Master Blades to actually have an exact origin. Birth, was the blade Ana herself, used to create the world. It's location is unknown, but some believe it can be found at the center of the world.
The Birth Blade of Tai Ishikawa's mother. Crimson Snow is the sharpest blade in the world, and it cuts anything within an inch of the blade. However, the blade also has a blood price. On the first day of winter, the sharpness of the blade turns on them, (even if they are not in the presence of the sword), inflicting a grievous wound. Tai's mother carried out this "ritual" and survived it for over a hundred years.
One of the more known blades, Demise grants its wielder unimaginable power. However, Demise is also known as The Cursed Blade, because its master always met with a horrible fate eventually.
The Black Blade. The personal weapon of Raith Duskfall. How he came to have it in his possession is unknown, but it has been his signature weapon for centuries. When one thinks of either, they also always think of the other, to the point where The Black Blade has become a title for the mighty warrior. Dust has the power to, as its namesake, turn anyone or anything it cuts into dust.
A blade that grants the user control of the fury of the skies, to unleash devastating storms. Is located atop the highest peak of the highest mountain in the world.
The Burning Blade. It presents itself to a person who lays dying after suffering a horrible betrayal. It then binds with them, and keeps them from death, giving them the opportunity for revenge. After their quest for vengeance is complete, they finally die, and the blade disappears.