Third Sith Civil War

The Third Sith Civil War (282 ABY) was a major galactic conflict fought between the Mulier's Sith Regime and the Medeis' Sith Regime.

Prelude
After Darth Tempus' death and their defeat in Tempus' Sith War, an argument over who should now lead the Sith Empire and the Sith Order.

The two most prominent candidates were Darth Mulier and Darth Medeis, the only Sith Masters who survived the war.

War
Eventually, the arguing led to a tear in the Empire and a civil war between the two Sith Lords' regimes. Mulier's regime was beating to a pulp throughout the first half of the war. Mulier sent a distress call to Marotan asking Lucious Cotte for help and to put an end to Medeis' Sith Regime.

Cotte answered the call to help and eventually lead the war to a stalemate, when he confronted Darth Medeis. They agreed to a duel and whoever would win their regime would take control of the Sith Empire and win the war. After intense fighting, Cotte finally defeated Medeis by impaling him and then decapitating him.