Guessed by @Ultrashroomz
I feel like I haven't given this game enough credit over the years, mostly because of a second playthrough where I wasn't feeling it. And maybe it really isn't very replayable, but, who cares. It was amazing the first time through, it's an amazing entry in the Metroid series. Maybe it does get a couple things wrong about what the franchise is supposed to be, but it gets so much more right. In all truth, this is the game, the only game in the whole series (not just the Prime games), that really felt like it opened up what Metroid is. It widened the scope on so much of this universe, what kinds of planets, wildlife, histories, civilizations, we get to know so much more. Nothing else in the franchise, not in the 20 years that preceded or in the 15 years since, has come close to this one in that sense. To be fair, keeping things a bit smaller in scope is probably for the best, both in terms of gameplay and atmosphere, but we all had our wildest dreams of how much more ambitious a Metroid game could be, and Corruption is exactly that. It's the Metroid game that dared to dream.