The way I see it, the all-too-easily-dismissed element of surprise is key in the Ridley encounter. Even though I don't particularly buy the premise of the Space Pirates having been annihilated, that premise is there all the same. And under that premise, nobody is left to revive Ridley, so Samus would believe she'd put him behind her. The worst possible time to face your fear is when it's by surprise.
Why wouldn't Samus get equally upset the first time he's revived - Metroid Prime 1, I think? - when she's bound to be just as unprepared for his return?
In Prime 1, Samus witnessed Ridley on board the Frigate Orpheon (and again in Phendrana, IIRC) long before ever doing battle with him. So, yeah, cat was out of the bag. There's also no telling how familiar she is with Pirate habits in regards to resurrecting defeated leaders.
And, are we dismissing Prime 3's Pirate Home World canonicity? I mean, they weren't Zebesians, but Ridley was a Space Pirate leader, wasn't he?
Other M seems to refuse to acknowledge the Primes, although quite frankly with or without the Primes I have a few issues with their canon as to how they depict the Space Pirates.
Whether you're acknowledging Prime 3's Pirate Home World or not, the Pirates as a whole AREN'T Zebesian. Zebes was a Chozo Colony as well as Samus's childhood home after K-2L. Presumably Other M is using the term as short-hand for "Zebesian Space Pirate", as in those which were bred there, but that only further emphasizes the oddity in an interplanetary race being destroyed as the result of losing one planet.
Then again the Pirates work [tornado fang]ing fast. In Zero Mission he lands like 4 hours in, then you kill him shortly after, then some 2-4 hours later you fight MECHA RIDLEY!!!
I think that's less speed and more vanity. "Mecha Ridley" having no organic components, I see it as a part of the mothership, which Ridley commands, that was designed in his image.
The wiki claims that the Pirates that conquered Zebes (and altered themselves to live on it, according to the manga) renamed themselves Zebesians and considered it their home world, though they were still basically Space Pirates.
Again, Pirates being bred on/modified for/otherwise tied to Zebes is not the problem. The problem is how exactly does Zebes' loss equal the death of ALL Space Pirates? It makes absolutely no sense because Zebes was lost twice, once in the original and once in Super. Granted in the original, the entire planet didn't explode, but having bombed their base and their mothership I think it's a safe bet that they were routed from the planet. So the fact that they survived its loss once but couldn't survive the same loss again is exceptionally hard to swallow.
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