Metroid Metal. Listen to this band to know the definition of those two words. Of course, my favorites on Other Album are the Super Metroid tracks, with "Maridia (SM)" taking a huge lead in my own playlists.
Whenever someone asks me about the best bands creating video game music arrangements, my mind always turns immediately to the math metal stylings of Metroid Metal. Ever since Stemage belted out tunes solo under the guise, I've been enamored with the lovingly rearranged music contorted into headbanging tracks that would have had my teenage metalhead self crying in ecstasy.
Download it on Bandcamp for $6 or grab the digipack for an extra $2.