AMG isn't cut out for metal. Look up their entry for Death and you'll see why. They have the genre listing as rock and the following listed under 'Styles':
* Death Metal/ Black Metal
* Heavy Metal
* Progressive Metal
* Thrash
That's too inaccurate coming from a site that thinks of itself as an Encyclopedia for music on the internet and is supposedly made up of world class music journalists.
I personally let my ears guide me on genre identification and then verify it on Metal Archives, MR and assorted discussion on the internet.