One Of The Geniuses Behind Candy Crush Explains Why Some Levels Are So Tough To Beat

All eyes have lately been on King.com, the game-maker that delayed its IPO because Candy Crush Saga has been "too successful."

But before Candy Crush Saga became a massive hit on both Facebook and mobile devices, King.com had a few duds, King chief creative officer Sebastian Knutsson tells Business Insider.

Candy Crush Saga, Knutsson says, is essentially the result of the best elements from its most successful match-three games.

Bubble Saga, which launched at the end of the first quarter of 2011, was King's first big hit on Facebook.

"That's when we rebuilt and moved to mobile," Knutsson says. "We invested in how to make games work cross-platform."

As Candy Crush Saga players are used to, Bubble Saga also had strong visuals and the deep voice that tells you when you're doing well in the game.

"The first iteration had more of a humorous French accent, but the players hated that," Knutsson says. "So we changed it to a more classic voice. The current voice works much better."

Still, a lot of what King does in Candy Crush Saga, Knutsson says, it has not done before. Take the Dreamworld as an example.

Back in December, King launched its first major extension of Candy Crush Saga. Any player who makes it past level 50 can access the new Dreamworld area by tapping Odus the Owl on the game map.

"It was like a Christmas gift for our players," Knutsson says. "The majority of players are stuck at certain levels. Depending on where they are, they might feel frustrated. With Dreamworld, you can replay levels you've already beat and get rewarded with more content."

Speaking of being stuck on levels, some are much harder than others. Level 110 is a notoriously hard level, but level 111 is a breeze. That might seem a tad strange, but it turns out there's a reason for that.

"If the game becomes harder and harder forever, it will become unplayable," Knutsson says. "The test of that is making it for the players who complete game. The majority of players at end of the game have never paid. We never want to design a level that's unbeatable or that you would have to pay to complete. That's not our goal. Finding that mixture of pleasure and pain is the goal behind level design."

Another feature, depending on how you look at it, is getting locked out of the game when you run out of lives.

"A lot of players like it that you can't play forever," Knutsson says. "It gives you an actual break, which is good long-term because you don't get tired of the game. It gives you a natural pause."

Candy Crush Saga is King's most popular game, and it has been downloaded 500 million times. Since it launched in 2012, people have played over 150 billion games of Candy Crush Saga.

King's two most popular games are match-three, Knutsson says, but it wants to eventually evolve its network of games. Regarding an IPO, Knutsson has no comment.