The "elegant design" of Super Mario Bros levels has inspired devs for over 40 years, but it was Super Mario 64's 3D leap that was a "watershed moment"

Above all else, the driving force behind Mario's success is exquisite game design – something that is acknowledged by players and game designers alike. "Mario games have a timeless charm and wide appeal whether it's 2D or 3D," says Philip Oliver, who along with his twin brother Andrew is a veteran developer with over 40 years in the business. "Objectives are obvious, rewarded en route and praised when completed. Enemies are interesting, individually not too tough, but get progressively more challenging based on abundance and locations. Even when you 'die', it feels fair. Not something that can be said of all games, especially back then!

"I first saw Super Mario Bros on the NES at CES Jan 1990 in Las Vegas, by which time it was already a monster hit," Philip remembers. "It was such a beautifully elegant design. The objective was clear: get to the end on the right, but enemies and obstacles, of increasing difficulty, will make that a challenge! With a simple console control pad and its limited buttons, there was no learning time involved and there was nothing intimidating about it at all." Inspired by this, Philip and Andrew began to write NES games, citing Dreamworld Pogie as one that is a particular homage to Super Mario Bros. The lack of learning time Philip mentioned is one of the most famous aspects of Super Mario Bros, in fact. On the very first screen, the game introduces you to all of the fundamentals – enemies, regular blocks, Question Blocks and mushrooms.

Even in the original Super Mario Bros, that left plenty to discover. There are varied environments with their own unique challenges, confrontations with Bowser and so many secrets to find – underground areas in pipes, beanstalks leading to the sky, Warp Zones beyond the usual end of the stage and more. Ingenious little touches like platforms connected by pulleys were the start of fantastic gimmicks employed by later games, including floating rafts and platforms that moved along rails. Likewise, enemy behaviours became more interesting, most notably with the Boos which wouldn't move if Mario looked at them.

Moving to 3D posed twin challenges for platform game designers. "Keep the controls simple and the objectives obvious, whilst not appearing to be too simple or condescending," says Philip. "In the early Nineties, game designers, particularly Andrew and I, debated how character platform games, our speciality, could achieve both these when translated into 3D," he recalls. Super Mario 64 was a "watershed moment" according to Philip, who feels that 3D Mario games avoided unnecessary complexity and "only take the advantages of that third dimension and the gameplay and visual opportunities it presents".

In shifting to 3D, Nintendo could have chosen to retain the linear obstacle courses of the 2D games – indeed, games like Crash Bandicoot had plenty of success doing just that. However, Nintendo reimagined the Mario formula and introduced open 3D spaces with a variety of routes and goals. "One of the breakthroughs they made was the way they handled the viewpoint camera in the 3D space," Philip explains. "It had its own logic to ensure the player got a great view of both Mario and the challenges ahead, but not simply by being locked behind him at a set distance and angle. This made it visually so much more attractive and easier to play."

One particularly strong aspect of the Mario games is that you never need to do absolutely everything, which serves a dual purpose. It serves as a way of circumventing frustration, by allowing players to simply avoid challenges that they struggle with, and it ensures that there's usually plenty of life left in the game after Bowser is finally toppled – completists will rejoice in finding all the exits in Super Mario World, or as many as 50 additional stars in Super Mario 64. In a series that appeals to such a broad range of players, that level of optional depth is essential.

Of course, Nintendo did eventually try more traditional obstacle course designs in Super Mario 3D Land and Super Mario 3D World. But no matter whether designing in 2D or 3D, Philip feels that the principles that underpin a good Mario level are universal. The first is to feature "[an] obvious objective, obvious route, obvious enemies and obstacles". The second is to ensure that "difficulty and duration of the level are directly proportional to how far you are into the game". The third is to engage the player with "micro rewards often (coins), occasional mini rewards for completing a section, and finish with a grand finale and big reward". Just imagine sliding down that flagpole and fireworks erupting before you turn the page, and you'll see exactly what he means.

A Q&A with Official Nintendo Magazine's Matthew Castle

RG: What makes the level design in Mario games so strong?

MC: It helps that they're built with the best building blocks around. Not just Mario himself, always a joy to control, but the enemies, toys and gimmicks that pepper levels from Super Mario Bros onwards. Crucially, the designers understand the importance of a hook – giving every stage a unique challenge, a new enemy type, a visual surprise or a setpiece that combines all of the above.

And then sprinkled over the top you have the meta strangeness – the secrets aimed at the fans who really drill into these things. That Nintendo were already doing this in Super Mario Bros seems so wild to me – the idea of leaping out of the level to run along the top, and to be rewarded for it, is such an out there idea. But here it is, smashing apart conventions that the game had only just introduced.

RG: Where games like Crash Bandicoot tried to adapt the linear assault courses of 2D games into 3D, Super Mario 64 adopted levels with multiple goals and fewer set routes. How important do you think that change was?

MC: It seems inevitable to me that giving Mario 3D movement would require levels that pull him in every direction – you'd be squandering that technological evolution otherwise. Weirdly though, it does seem to trigger a tug-of-war between more traditional linear platforming and explorable land masses – one that's ongoing to this day. Even within Mario 64 you start with the wide-open plains of Bob-omb Battlefield and slowly work your way towards more abstract spaces like Rainbow Ride.

As much as 64's worlds wowed me originally, I think Nintendo did something more interesting with 3D Mario when they started to prune back levels and focus on the moment-to-moment leaps and bounds. I don't want to reduce it to a crude 'jumps per minute' count, but Galaxy and 3D Land/World feel more like platformers from the amount of time you spend worrying about what's under your feet at any given moment.

RG: Where Super Mario Sunshine and Super Mario Odyssey changed Mario's 3D platforming tools, the Super Mario Galaxy games focussed more on a different kind of environment. How do you think these approaches compare?

MC: There was a time I would have said 'keep Mario pure' – transformations are one thing, but permanently altering his moves with a jetpack dependency felt like it was undermining one of the most purely enjoyable movesets in the platforming biz. Galaxy, which only really adds a spin jump to his repertoire, felt like a beautiful advert for what 3D Mario should be. The levels actively made Mario's moves more interesting which is a distinctly Nintendo bit of wizardry.

But again, Odyssey showed us a third way. The problem with Sunshine isn't the concept of a platforming tool, but the specific vagueness of FLUDD – Cappy feels more reliable and lets you do some unbelievable things as a result. The genius bit of Odyssey (or one of many) was including the Time Trial Ghosts so you could see what faster players were doing with that magic hat to chuck Mario round those levels at speed.

Want to play some of the plumber's best games? Check out our best Mario games ranking!