"wfz brought up a good point that the whole "but they're invulnerable to ice" thing was probably a lie that Adam made up, an excuse for shooting Samus, when his real purpose was merely to make Samus unable to stop him from sacrificing himself, especially given that they weren't invulnerable to ice anyway."
It's one thing to assume a character is lying, which would be plausible enough on it's own but not great writing if it is never shown to the player. However, it's another thing to assume he's lying while the game shows you imagery of Metroids being genetically enhanced . In that case you are not simply assuming that Adam is lying, but that the game is deliberately deceiving the player with cheap tricks, which is not only a bigger assumption but one that doesn't exactly help the Other M narrative argument.
The "endless supply of Metroids" could be an issue in Prime for plot continuity though it has a lot less problems than Fusion or Other M, though I don't think they really presented that. In all three Prime games Metroids still ended up being something you found relatively late in the game, and only once you had gotten deep into the Space Pirate's laboratories. Their presence is always tied to the presence of Phazon, which is probably the real plot hole as Metroids seem linked to Phazon in the Prime series while in the manual for Metroid Fusion it's claimed they were 'created' by the Chozo.
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.
