A Metroid Tip
http://www.gamefaqs.com/console/gamecube/file/447244/35934
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NOTE: Some players (including Kai, who pointed it out to me) have reported
encountering Fission Metroids in the caves on level 3 after getting the Phazon
Suit. These look like regular Metroids except that they are colored, with the
color corresponding to one of your beams. I haven't seen them here, so maybe
whether you see them depends on the version of the game you have, or maybe I've
just never gone back in these rooms after getting the Phazon Suit. If you find
Fission Metroids in these rooms, I'd recommend staying out of them unless you
absolutely positively have to go through. If you do, check the Creatures
section below the walkthrough to see how to defeat them, or just try to get
through the room as fast as you can and avoid them.