Sith Lord Renning is one of the most important questgiver NPCs on Korriban, not for gameplay but for the latter SWTOR lore released through later expansions.
The Sith Lord was fascinated with the research of animal experimentation, especially of the Tuk’ata found on Korriban. He enlisted the help of a Sith Warrior or Sith Inquisitor to investigate whether or not his work was being undermined or sabotaged by his apprentice, Malora, during this time.

While Renning had 3 known apprentices, Malora, Dominique and Elizhis, only his two female apprentices (Malora and Dominique) would rise. Many years later his apprentice Malora would rise to the rank of Darth and sit on the Dark Council in charge of the Sphere of Scientific Advancement, where her own research on bioengineering and sith alchemy would culminate in the mutation of Geonosians to be used as tools of war against the Republic on Ossus.
Dominique would forever live in the shadow of Malora and eventually turn to Lord Valeo and Kanoth in the creation of Nihrot and overtaking the Mass Shadow Generator.

In 16 ATC, the Revanites tricked both the Republic and Empire into attacking each others force homeworld simultaniously. While many Sith were away invading Tython, only a small group of Overseers, Sith and Councilors remained on Korriban. Lord Renning held the invading Republic forces away from the major turbolift from the Valley of the Dark Lords to the upper Turbolasers and Landing platform closest to the Korriban Academy.
Renning used both his martial skills as well as his Sith Beastmaster training in an attempt to control a horde of domesticated Tuk’ata to overpower the Republic attackers, however he failed and was slain in battle.