Taken from this months Edge magazine:

When I was younger, I was really into action games, so when designing a level, I thought about creating levels that I would want to play. What I learned about level design while working on Super Mario Bros 3 was really how to make levels that were enticing – that were fun and exciting because they presented challenge. But also balanced that with the ability for them to be completed with a reasonable amount of effort so people wouldn’t get angry or quit. I wanted the levels to be played from beginning to end, and working on SMB3 was a really great way to balance all of those things to make something that was fun, but also something that people could complete. …It’s exactly what we did when designing levels for example, on SMB3, not actually in tandem with a testing team but within our own development team.

So if I was working on creating a level, I’d get someone else from the team, maybe someone working on the artwork or some other job, and get them to play the levels. We’d observe them as they played and think “Oh, this one section is too difficult” or “this level concept doesn’t work” but the most important thing I watched for was if they were having fun or not. It didn’t matter so much if they were able to clear the level or not clear the level by its design, as long as they were having a good time while they tried. This process was repeated over and over and over again with different participants of the team until we came up with the final level, one that would be completed comfortably and one that was fun to play consistently. – Katsuya Eguchi

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