Distant Sun is a Russian band that's been around for a few years and their debut album is called Dark Matter. When I first spun the album and the opening track "Prophet of the Sun" was almost finished, my initial impression was of a Testament clone. The vocals are a furious yell, the riffs thrashy and the atmosphere black and grim all of which brought Dark Roots of Earth to mind. Then Distant Sun sort of turns things on its ear and the drums pick up to double-kick speeds on later tracks and while the mood doesn't shift to flowery by any stretch it becomes clear this is Power/Thrash. I have to admit my first listen left me cold but Dark Matter has improved with every spin and is actually a pretty fun album.
If you like old Helstar or Vicious Rumors Distant Sun is band worth checking out. They don't push the envelope much on Dark Matter but do some good work within the confines of the genre.