In the beguiling indie game What Remains of Edith Finch, released earlier this year, you can swing on a swing, fly a kite, conduct a frog, swim as a shark, fly as an owl, reach with a tentacle.

There’s fish-slicing, picture-taking, holding a hand out of a speeding car’s window, and a lot more, all within the space of a game that takes perhaps three hours to play from start to end. Oh, and there are full first-person controls, too, for Edith herself.

[NOTE: MANY SPOILERS FOLLOW]

All in all, this one game has something in the order of 30 different control schemes, depending on how you categorize them. And yet there are no tutorials. You play instinctively, exploring the controls as you go along.

"A big part of how the game works is finding a good balance of that complexity, where it feels like you're being asked to do ridiculous, complicated and unusual things and yet you're succeeding, succeeding at a rapid pace, so when you look back even over the last 10 minutes, it's like, 'Oh! I was flying a kite and now I'm chopping fish and it feels like Alice falling through the rabbit hole,'" creative director Ian Dallas says.

"Whatever you thought should be the way it works will be the way it works for you."

Getting the game to this frictionless point was as hard as you imagine it might have been. It took many iterations of its various elements as well as various creative solutions for taking player inputs.

Whole sections of the game hung in the balance as developer Giant Sparrow, which had previously made first-person painting game The Unfinished Swan, struggled to marry narrative-bearing gameplay with seamless controls.

If there's any kind of neatly packaged catch-all solution to the challenge Giant Sparrow set itself, it was to try to make the game work in the way people expect it to. On the small scale, that meant helping players by assuming what they want.

"Whatever you thought should be the way it works will be the way it works for you," says Dallas. So if you need it makes most sense to face a ladder and push up to go down it, or to push down, the game takes whatever your first input is and remaps the controls, assuming that's how you expect the controls to work.

Not all games can make assumptions about player intention like this, but What Remains of Edith Finch's environments and interactions are carefully constrained, with player input restricted to two analogue sticks and the trigger button. The aim was to create trust in the player that they’d never be asked to do anything outside these three inputs.

"Hopefully for players that means that once they identify that pattern and they trust those buttons. Discovery and surprise comes from how using the same buttons gets wildly different responses back from the game," says lead designer Chris Bell.

"There's no meter or explosions when you do it perfectly. We’re asking for very different things in each of the stories."

Securing that trust in all players wasn't straightforward. Dallas remembers during playtesting how players would mash all the buttons when they got frustrated. "There's some kind of triumph of the human spirit thing in there, so even though pressing triangle never did anything, people are like, all right, this is the time triangle is going to save me," he says, laughing.

At the same time, they'd notice when players did relax into the controls, they'd sometimes go too far and not realize other inputs were also valid. That was true for Calvin's story, in which players use the two analogue sticks to move Calvin's left and right legs to help him swing. Only by using both sticks could they generate the speed the sequence required, but they'd get enough feedback from using one stick that they'd keep using it without trying the second to see if it also did something.

The solution was to reduce the extent to which players would swing when they used only one stick. "People were thinking, 'Maybe I can do this just a little bit better'," says Dallas. "Because there's no meter or explosions when you do it perfectly. We're asking for very different things in each of the stories."

"We tended not to worry at all about the story or the character or anything until we had a clear beginning, middle and end for the gameplay progression."

Calvin's story was otherwise one of What Remains of Edith Finch's more straightforward sections. Like most, it came from an idea for interaction: the experience of being a child on a swing. This was then passed to a designer -- Ben Esposito, developer of forthcoming physics toy Donut County and many other artfully playful games -- who developed several prototypes in Unity.

Early on, the team focused on the idea of each stick controlling a leg, and then it was a matter of tuning. "We tended not to worry at all about the story or the character or anything until we had a clear beginning, middle and end for the gameplay progression," says Dallas. "Once that was working, we thought about who this event would occur to."

A far more tortuously designed story was Lewis,' in which players are asked to cut fish heads off with one analogue stick while simultaneously moving a character in a separate 'imagination' world. It's the game's stand-out story, situating an affecting narrative in perfectly complementary interaction. The trouble was complexity.

"Because we were looking at that mechanic in isolation we didn’t appreciate that it was a piece of lots of other things that the player would be experiencing."

Giant Sparrow's aim was create the experience of being bored in a monotonous job, and they soon decided it would be set in a cannery, with the main action being based on preparing fish.

"There was a boss who was wheeling around checking on work, you'd take a fish off the conveyer belt and look if it was a good or bad fish that was rotting," says Bell.

"You might take the good ones off the line and start fileting it in a far too elaborate process, trying to get the slices just right. And then you had to sort parts of the fish into good and bad piles, and when you hit your quota your boss would come and hand you a new bucket. The whole thing was absolutely horrendous and I don't know how the hell we went that far before we were like, 'What in the world are we doing?'"

Realizing the mental overhead with which players were being loaded as they played the fish-cutting game and the imagination game at the same time, while also absorbing the story itself, Giant Sparrow realized it needed cut out the complexity.

"Because we were looking at that mechanic in isolation we didn't appreciate that it was a piece of lots of other things that the player would be experiencing," Dallas says, admitting the team feared that having less to do would fail to sustain players' interest.

From an external point of view, it's surprising that there's barely any reuse of the programming and design of controls across all the different ways you play What Remains of Edith Finch. But each system is so custom that there wasn't any benefit. "Doesn't the underwater version of the bathtub story share the controls with the shark?" Bell asks Dallas.

"It initially did, I just copy and pasted the code, which is very advanced level software engineering," Dallas replies. But it was only 30 lines or so, given that the frog needed a camera that could look around, and the whole story was completely revised several times over during its development anyway.

"Like baking bread by taking a little bit of the mama sourdough starter," is the way Dallas describes the approach, which involved entirely rewriting the original Unity prototypes for the game itself, which uses Unreal Engine.

"There's always a desire to save things, to port over the exact code you used in your prototypes," says Dallas. "But I think there's some advantage in starting over and the player controllers benefited from that, taking the lessons learned but not the actual code.

"Everything else in the game is custom, and not because we necessarily hate efficiency," says Dallas, "it's just genuinely the most efficient approach when things are constantly changing. You don't necessarily want all your ladders be the same and you have only three ladders, so it doesn't make sense to make a ladder system. So there's a lot of custom stuff, but not because we were obsessive about it, but because by the nature of constantly throwing things out it helped to have these agile, spry little nuggets that we could plug in."

"The tricky part was finding something that was a mechanic that players could explore but also we felt there was a story to tell with it."

Despite all these discrete pieces, there's a consistent feel to What Remains of Edith Finch, a languid smoothness, something Dallas puts down to his use of harmonic springs rather than smooth-stepping through interpolation.

"We have springs, or springs connected to other springs, that have an inherently organic and pleasing feel to them, and can be tuned as well," he says.

The owl's camera snaps a little more, while Edith's first person controls are gentler, both a function of organic systems in which nothing stops or starts on a dime and which Dallas hopes feel graceful.

From What Remains of Edith Finch's three inputs the game extracts vastly different results, and Dallas believes there are many more to be discovered. "Probably an infinite number, but the tricky part was finding something that was a mechanic that players could explore but also we felt there was a story to tell with it."

Even stories that sound promising were left behind, such as Bell's idea for one about a sister trying to stay calm as her twin brother is leaving home to go to war. She lies in some grass and experiences the world, which is flipped 180 degrees, falling away. By breathing she'd be able to grab on to things and control her anxiety.

"Maybe it would've worked," Bell says. "I think part of it was the initial approach might have been flawed in that when you're actually laying on the ground, the blood is rushing to your head and you're physically there, versus when you're sitting upright looking at the screen and the character's screen is flipped 180 degrees, there's more of a disconnect."

"But nothing that we looked at in all the prototypes did we feel was so close, if only there was this one thing," says Dallas. "They all had tons of problems." What Remains of Edith Finch consistently proves over its three-hour running time that converging compelling stories, compelling game design, and controls that anyone can wordlessly grasp is a delicate art.