Eighteen rock/metal musical tracks.

OST 3 Preview: https://www.youtube.com/watch?v=aI9LuZ-N-Hw&list=PLoYqlzL_XZtLeK-V4xeXBN_kMwUABkm8s

OST 4 Preview: https://www.youtube.com/watch?v=LVr6vju4_LM&list=PLoYqlzL_XZtI6b5JhmRfPtmLy9X65sffX