Dark Blademaster

"I am beyond any title the Sith have given their followers. I shall be known as a Sith Blademaster, undefeatable with the blade."

- Darth Horibilis in his personal journal

Sith Blademaster was a title the famed Darth Horibilis gave himself when he realized that he was undefeatable with the blade. No other Sith on record has ever become a Blademaster, because Horibilis' apprentices could never defeat him in their final test, meaning he could never really become a Sith Master, so he became the Blademaster of the Sith. Darth Horibilis determined that a Blademaster would have to have killed hundreds of Jedi using his own blade, and to have extreme Force prowess so as to enhance blade attacks. Darth Horibilis fit this profile very well, having cut a path of carnage through the Galaxy hunting for Jedi.