Ridley does not make any appearance at all in Metroid Prime 2 Echoes, and the Phazon beam is ONLY in Metroid Prime, the first one, and it is only active when you are standing in a pool of phazon, which is only at the end of the game.
For those that don't know, Metroid Prime is actually Dark Samus, at the end of Prime 1, Metroid Prime rips off Samus's Phazon suit when it is dying, trying to pull her in with it, but it only takes the suit, and it then makes a shell of the suit and hides in there.
If you complete Prime 1 at 100%, you will see the little teaser at the end with Metroid Prime poking something out of the ground to show it is still alive, and thus becoming Dark Samus.
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Updated to this post
10/08/2007
Metroid Prime 3: Corruption
Behind You....