Nintendo's Shigeru Miyamoto found it hard to watch his own kids playtest Super Mario 64: "Geez, does this kid have any brains?"

Children take after their parents in all sorts of ways, but one of games industry icon Shigeru Miyamoto's children may not have inherited their old man's gaming pedigree as Super Mario 64 playtesting revealed.

In an interview originally featured in Japanese strategy guides and now available on Shmuplations, the legendary developer and producer of Super Mario 64 discussed the game's development at length. When discussing playtesting, Miyamoto revealed that the team had a group of 10 middle schoolers, including his own child,  play around on King Bob-omb's stage, Bob-omb Battlefield.

Unfortunately, it appeared that Miyamoto's gaming pedigree may have fallen rather far from the tree, with his child's performance leaving something to be desired. "Seeing him try dozens of times, over and over, to get up this unclimbable hill, as a parent I couldn't help but think, 'Geez, does this kid have any brains?'" Miyamoto laughed. Thankfully, the children's abilities (or lack thereof) aside, the playtest had been a success. "Afterwards we asked the children what they thought of the game, and they said it was fun, and that they wanted to play it again."

Instances like this influenced Miyamoto and Nintendo's approach to games, creating a focus on fun being the most important aspect. "I think there's been this image with games that if you can't beat it, it's not a fun or good game, right?" he explains. "That's a philosophy we've stuck to at Nintendo, too, but I figured that if a game was this fun to play even if you weren't getting anywhere, well, it must be alright. Until this game, I was very sceptical about something like this being fun."

Check out where Super Mario 64 fits in our list of the best Mario games of all time.