A collection of all the Sith Themes from the Old Republic to the New Trilogy. Timestamps below

The Old Republic
0:01 Darth Malak's Theme (KOTOR)
5:03 Darth Revan's Theme
8:31 Darth Nihlus' Theme (KOTOR II)
11:36 Darth Sion's Theme
14:24 Darth Traya's Theme
16:08 Darth Malgus' Theme

The Clone Wars
18:26 Darth Maul's Theme (Duel of the Fates)
22:41 Savage Oppress' Theme
24:35 General Greivous' Theme
29:07 Count Dooku's Theme
33:15 Asajj Ventress' Theme
37:24 Darth Vader's Theme

The Imperial Era
40:53 Darth Vader's Theme
43:58 Second Sister Theme
48:07 Seventh Sister Theme
53:05 Starkiller's Theme
58:04 Eighth Sister's Theme
1:00:32 Emperor Palpatine's Theme

New Trilogy
1:04:06 Kylo Ren's Theme
1:09:05 Snoke's Theme

1:11:07 Sith Lords (KOTOR II)