Things of Sword of the Brotherhood

A magical weapon created eons ago by either gods or beings who had the power of gods. 

Unlike other magic items, the Sword of the Brotherhood does not have a finite power. Its power actually depends on the one wielding it. The Stronger the wielder, the stronger the sword.

The Sword also had the ability to adapt its powers in combat to gain an edge in combat against any foe... if one knew how to use it.

This made it one of the most sought after Magical Weapons of all time, as it was potentially the most powerful weapon known to man kind.

No one living today knows why the sword was created. As it doesn't seem to have a preference for good or evil, some scholars say it was made to be the ultimate test of character. Some say it was just created to win a great war that supposedly happened thousands of years ago. Again, no one really knows.