The NES Classic Edition series of interviews, featuring classic Nintendo games and the developers behind them, culminated today in a final interview spotlighting the developers behind the original Metroid.

Director Yoshio Sakamoto-san and character designer Hiroji Kiyotake-san sat down to discuss everything that went into creating Metroid, including development and their ultimate decision to make Samus Aran a woman.

When asked how it is they came to develop this game, Kiyotake-san describes that as we were working, the Super Mario Bros. "boom" was happening. Recognizing this, he wanted to make something Super Mario Bros. didn't have in order to complement it,  starting with movements that Mario didn't do:

What Super Mario Bros. didn't have? Like what?

Kiyotake-san: As a simple example, you know how Mario slides a little before stopping?

Uh-huh…

Kiyotake-san: So we tried to make a dead halt.

You began with movement?

Kiyotake-san: Yes. We wanted to make actions that Mario didn't have. And then…

Sakamoto-san: Aren't you forgetting something important?

Kiyotake-san: Am I?

Sakamoto-san: Super Mario Bros. is about avoiding enemies.

If you touch one, you lose a turn.

Sakamoto-san: In response to that, Kiyotake-san was complaining, saying, "Why do we have to avoid them?!" (laughs)

(laughs)

Sakamoto-san: When you began making Metroid, you wanted a technique called a Screw Attack for doing a spinning jump to defeat enemies. Isn't that right?

Kiyotake-san: Oh, that's right! (laughs)

When asked how they decided to make Samus Aran a woman, the developers simply thought about something that would really surprise players at the end of the game. Additionally, they wanted the reveal to be a type of reward players earned for clearing the title:

How did you decide to make Samus Aran a woman?

Sakamoto-san: Once we entered the final stage of development, we started talking about having different endings depending on how long it took players to clear the game. We wanted to prepare a reward for people who cleared it more quickly.

Kiyotake-san: We wondered what would surprise everyone and talked about removing Samus's helmet.

Sakamoto-san: Then someone said, "It would be a shocker if Samus turned out to be a woman!" And everyone thought that would be interesting and wanted to do it, so we decided it right away.

Kiyotake-san: Yeah, we decided that in a flash. Back then, people played games over and over, so we wanted to give a reward for playing through quickly. Then we decided to put in four endings, with Samus removing her helmet or her suit and so forth.

As they played, everyone thought Samus was a tough, musclebound guy, but they learned in the end that Samus was a woman.

Sakamoto-san: People who played it back then were shocked. And even now people talk about it like a kind of legend. (laughs)

The full in-depth interview can be found here. Metroid celebrates its 30th anniversary this year, with the last entry in the series releasing this past August in Metroid Prime: Federation Force.