Metroid stage design in a nutshell...
64...
Developer 1: Hey guys, we're missing a Metroid stage!
Sakurai: I hate Metroid. We don't need a Metroid stage.
Developer 2: But Samus needs her own stage, doesn't she?
Sakurai: ...Fine. I played Metroid before. Isn't it that game with the caves and lava?
Developer 1: Well, I was thinking of the Crateria setting from Super Metroid, or some of the more vibrant Brinstar sett-
Sakurai: Nah, let's just make a stage in a cave with lava.
Developer 1: But Brinstar...
Sakurai: Okay, we'll call it Brinstar.
Melee...
Developer 2: Hey, let's add another stage for each returning franchise!
Sakurai: Sounds good to me; I'd love two Kirby stages.
Developer 1: For a Metroid stage, I was thinking something set in the greenery of Brinstar, with Kraid walking around in the backgro-
Sakurai: Don't we already have a Brinstar?
Developer 2: Well, he was meaning a Brinstar more like Super Metroid's-
Sakurai: Fine, we'll make another Brinstar stage. God, you guys love that place.
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Make it another cave with some lava and put this "Kraid" guy in the background. He's the short guy with the hair, right?
Brawl...
Developer 1: Oh my gosh, we have to make some cool new Metroid stages! There are a bunch of new Metroid games to choose from!
Sakurai: We already made two.
Developer 1: But...
Sakurai: What, you want another one?
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Fine. I'll go play through Metroid and see what areas catch my eye.
*...A few days later...*
Sakurai: Alright, the two main areas are Norfair and Brinstar. We've already done Brinstar twice, so let's do Norfair next. Norfair's a cave with lava, and you seem to love those.
Developer 2: What about Tourian?
Sakurai: What, you sneezin' or something?
Developer 2: Tourian, the last area in the original Metroid.
Sakurai: Stop talking like there's more than one of these games. Anyway, I didn't get that far, so make Norfair.
Developer 1: What about a level from the Metroid Prime series?
Sakurai:..........The what?
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Whatever, make another cave with lava.
Developer 1: But I'm sick of caves!
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I'm sick of lava!
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I want a cool and unique Metroid stage, like Phendrana Drifts, or Chozodia, or-
Sakurai: Fine, fine.
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Metroid's in space, right? Make a level in a space ship.
Developer 1: