Sith apprentice/Legends

"Tell me what you regard as your greatest strength, so I will know how best to undermine you; tell me of your greatest fear, so I will know which I must force you to face; tell me what you cherish most, so I will know what to take from you; and tell me what you crave, so that I might deny you."

- Darth Plagueis.

Sith apprentice was a generic title taken by a Sith if he/she was an apprentice. In Darth Bane's New Sith Order and the Rule of Two, the Sith apprentice and the Sith Master both held the title Dark Lord of the Sith simultaneously, unlike the earlier tradition of a sole Dark Lord (though it appears that the apprentice didn't assume the role of Dark Lord until their training was complete).

This allowed the Sith Order to continue its existence, because a Sith apprentice would kill his master and obtain an apprentice.

This, in effect, made even the "second" member of Bane's order the "equal" of the greatest Dark Lords of the past, like Exar Kun and Darth Revan.

Sith Apprentices before Bane's Order

 * Ulic Qel-Droma (apprentice to Exar Kun; left the Sith Order)
 * Darth Malak (apprentice to Darth Revan; usurped the rank of Sith Master from him)
 * Darth Bandon (apprentice to Darth Malak; killed by Revan)
 * Yuthura Ban (apprentice to Uthar Wynn; redeemed by Revan)
 * Bastila Shan (apprentice to Darth Malak; redeemed by Revan)
 * Visas Marr (apprentice to Darth Nihilus; redeemed by the Jedi Exile)
 * Darth Nihilus (died shortly after reaching the rank of Sith Master)
 * Darth Sion (died shortly after reaching the rank of Sith Master)

Sith apprentices in Darth Bane's Order

 * Darth Zannah (rose to rank of Sith Master)
 * Darth Cognus (rose to rank of Sith Master)
 * Darth Millennial (departed before he became Master)
 * Darth Vectivus (rose to rank of Sith Master)
 * Darth Plagueis (rose to rank of Sith Master)
 * Darth Sidious (rose to rank of Sith Master, having killed his master Plagueis in his sleep)
 * Darth Maul (died before reaching rank of Sith Master)
 * Vergere (fled after attempting to kill her Sith Master)
 * Darth Tyranus (died before reaching rank of Sith Master, betrayed by his master before he could set his own plans into motion)
 * Darth Vader (died before reaching rank of Sith Master, abandoned the dark side of the Force and returned to the light as a Jedi Knight)
 * Flint (abandoned the dark side of the Force and returned to the light side)
 * Carnor Jax (died before reaching rank of Sith Master)
 * Jacen Solo (apprentice to Lumiya)