Yeah, that's another reason I like both Metroid and Halo (although I've never played a 3D Metroid, so I may change my mind, but I doubt it with the new controller): The lack of blood and gore.
It's a bit strange that Halo is rated M because there is hardly any blood and no real gore (no decapitations or anything). Just a lot of purple-ish-blue alien blood and the Elites do make a loud groan when they die.
The Grunts are like little annoying kids, so maybe that's what gets the ESRB people angry.
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