With Zelda, I always thought that coming up with timeline theories was a waste of time. Because clearly with the earlier games they didn't really care that much how well the games linked up, and then with Ocarina of Time, you've got friggin' time-travel, which totally messes everything up. There is a proper timeline out there, but it's just not... interesting... to me to try to reconcile the games to each other perfectly.
(Spoilers behind the cut for various metroid games).
Then there's Metroid...
Which, like Zelda, was born out of the NES-era. And yet... it's done a better job at being relatively consistent. At least with Metroid, you don't have timeline problems.
But now that I'm 98% done with Metroid Prime 3, it's still interesting how each iteration kind of... reshapes the previous ones.
- In terms of the series as a whole, the Metroid Prime trilogy has changed the metroids themselves. It used to be that they were native to SR388 (later revealed to have been created or modified by the Chozo to stop the X parasites), and they had various physical attributes that were pretty consistent in the Metroid games. But now with the Prime trilogy, the metroids are different: they have a different appearance and a different life cycle. And they're much easier to kill. Complicating everything further, Metroid Prime herself appears to be a native of Phaaze, coming with the meteor rock to Tallon IV. That's all very clear from the Chozo Lore in Prime 1, and then in Prime 3 there are scans on Phaaze that support this as well. Metroid Prime then supposedly spawned some of the metroids you find on Tallon IV (while the Space Pirates brought some identical metroids with them from Zebes). And complicating things further is the fact that "Phazon Metroids" are supposedly phazon mutations of "Tallon Metroids." But if "Tallon Metroids" ultimately originate from Phaaze (the ones spawned by Metroid Prime) and SR388 (the ones brought by the Space Pirates), how much sense does THAT make?
Of course, then there's the fact that the same alien species essentially exists on multiple alien worlds. Shriekbats, anyone? There is even a robotic version of shriekbats on Elysia, which the game doesn't even pretend to try to explain.
In the end, we just don't have enough information to figure out how all these metroid forms are related. We can make up plausible explanations, but we just don't know.
I guess the closest we come to an answer is in Prime 3, when you go onto the Pirate Homeworld and in the first room with metroids you come across, there are a few tanks that talk about the metroids in them being removed to other facilities. And each one is basically implied to be something like a different species of metroid, each associated with a different game in the franchise.
The simplest explanation: plot hole. Haha. Just like Zelda... these things are not meant to be analyzed!
- Then there's Metroid Prime herself. The first game had her as coming with the phazon meteor. The third game would imply that she is the guardian the phazon chose to protect it while it infects the planet (and that the Emperor Ing... which was technically CREATED by the Leviathan when it crashed into Aether... was the guardian the phazon "chose" to protect it while it infected that planet). But basically in the first game, she's this... awesome, fearsome creature that is somehow behind the spread of the phazon corruption.
Then the second game basically turns her into this... evil doppleganger, which is just lame. It's also basically just the plot of the first game all over again, except with hokier sci-fi crap. Blah. I really didn't like the second game.
Then there's the third game. She's now more of an outright mastermind, engineering grand plots to be the conqueror of the cosmos. So I guess now that Metroid Prime bonded with Samus' DNA and the phazon suit, she's got intelligence, and can now do far more than when she was just "The Worm" of Chozo lore.
But even so, it's not really clear to me who's in charge. Is it the phazon, somehow the collective semi-sentience of all the phazon particles of the universe and Phaaze itself collaborating as some kind of superorganism mind, manipulating the creatures that feed upon it to do its bidding? Or is it Metroid Prime using Phaaze to conquer the universe? Either way, it's something clearly symbiotic. And I think it's Metroid Prime on top, particularly since she controls the bounty hunters and space pirates she corrupts, and well... she even controls the Leviathans via Space Pirate technology and Phaaze itself by implanting the captured Aurora Unit.
So basically Phaaze had very slowly and sort of mindlessly been trying to replicate itself by sporadically sending out these meteors. And then Metroid Prime comes along (part metroid, part Samus, part chozo suit, part phazon) with her new gift of intelligence, and she's able to mobilize everything phazon so that she can efficiently set herself up as the conqueror of the universe, replicating Phaaze quickly and intelligently by attacking multiple strategic Federation planets simultaneously (plus the Space Pirate homeworld).
So even though the Prime 2 & 3 feel like they're really just about the phazon, I guess there is a metroid masterminding it all...
(Please note that I refuse to refer to Metroid Prime as "Dark Samus." Haha.)
Kind of relatedly to all of this... I kind of wish they focused more on Metroid Prime over the Phazon, because well... if you're going to call the game "Metroid," make metroids central to the story, darn it. I don't like the idea of it being called "metroid" just because that's the name of the franchise. I'll bet most players don't even really know why the second two games in the trilogy are even called "Metroid Prime" in the first place; it really doesn't help that Metroid Prime is referred to as "Dark Samus" from the second game on.
In the end, all that matters is that Samus is still awesome.
Also: my Majora's Mask icon is bothering me... the way his left hand and left foot are off-screen is very disconcerting.