*) Korriban after the Hundred Year's Darkness.
The tombs of the leaders of this organization, such as Tulak Hord, were guarded by tuk'ata.  This organization carried out Operation Shadow Hand from Byss and A'Sharad Hett revived this organization after learning under XoXaan. This organization formed the Inquisitorius during its last period of power to hunt down potential enemies. This organization was officially founded on (*) Korriban after the Hundred Year's Darkness. The most famous government created by this organization employed Grand Moff Wilhuff Tarkin and its Rule of Two led to the death of Plagueis the Wise at the hands of his student who later issued Order 66 and is known for using "Force lightning". For 10 points, name this organization, the primary antagonist of the Star Wars universe. 
The tombs of the leaders of this organization, such as Tulak Hord, were guarded by tuk'ata.  
Sith Order (prompt on Galactic Empire)