During the Sith Crusade, Nathaniel Kenobi Solo was not a man known for his mercy. This led the many members of the Sith Order of Decreto to refer to him as the Scourge of Decreto.
The Scourge of Decreto: Nathaniel Kenobi Solo.
The name first began after a small skirmish between him and a small flotilla of Sith ships. Even though he had but one ship, Nathan was able to inflict heavy losses on his opponents' vessels.
Darth Abeonis eventually forbade the usage of his name in this manner, so as to not give his enemy a psychological advantage. Even still, his name was used in stories to scare raw recruits to the bone, and in turn, further strengthen them.