The Lost Twenty

The Lost Twenty, earlier known as The Lost, was the name particular to the Jedi Masters who had voluntarily resigned their charge and left the Jedi Order, usually over ideological differences.

One of the original members of the Lost Twenty was the Umbaran Jedi Master Phanius, who eventually became Darth Ruin, the first Dark Lord of the Sith in the New Sith Empire. Over time more would leave; twelve by 990 BBY.

The twentieth member of this group was Master Dooku, who left the Jedi Order in 32 BBY and became, unbeknownst to the Order until too late, Darth Tyranus.

Despite never having attained the rank of Jedi Master, Darth Vader considered himself to be the twenty-first member of this group.

Thracia Cho-Leem, the Master of Vergere, was not counted among the Lost Twenty, despite leaving the Order as a Jedi Master. The reasons for this are unknown. Some think this was because she stayed on the light side, though she never returned to the Jedi Order.

Along with the most venerable Masters, the Lost were remembered in the form of busts in the Jedi Archive ; a reminder of the Jedi's greatest failures, though the Jedi did not fault the individuals for leaving. On each bust's pedestal, the great deeds of the Master it commemorated were listed, though it gave no cite of why he or she left the Order.