The making of... Infinity Blade

It's been little less than a year since fantasy sword-fighter Infinity Blade shook up the App Store, but Utah-based developer Chair is back with an ambitious sequel that's bigger and bolder in just about every way.

To celebrate the release of Infinity Blade 2, we traced back its lineage and chatted to creative director Donald Mustard about the roller coaster ride of tech demos, Kinect experiments, and Apple keynotes that led to the creation of the iPhone's first mammoth game.

Infinity Blade's creation story starts in August of 2009, when Chair had just released Shadow Complex. The Salt Lake City outfit had put the finishing touches to the Xbox Live Arcade game - a Metroid-style adventure with a story penned by Orson Scott Card - and was thinking about what to do next.

"When we finish any game, we sit around for a few days and re-evaluate our list of games we want to make and decide what's next," Mustard says.

Chair has a wish list of potential universes, games, and stories it wants to investigate over the lifetime of the company. "We talk about that list and talk about changes in the market and system and all that stuff."

Kinect: Microsoft's Xbox 360 peripheral

Around this time, the industry was obsessed with Microsoft's body-tracking 3D camera thingy Kinect. It had been announced at E3 a few months earlier, and Chair thought about making a game for it. "Just as a brainstorming exercise, we said 'if Chair was going to make a Kinect game, what would we make?'."

The team looked at its list, and thought about a fiction that had been kicking around the developer for a few years. "We knew we wanted to do a fantasy style of game with a story that was a little more grounded in science fiction, and that we had logical reasoning behind our magic and fantastical creatures that you see."

Chair tested the idea with a Kinect prototype. "We came up with, basically, Infinity Blade. The idea of this sword-fighting mechanic which was more gestural-based, as opposed to pressing a button to do a sword slash," Mustard recalls. "We thought it was a really cool idea, and we moved onto doing other things."

An early demo of Unreal Engine 3 running on an iPhone 3GS

Almost a year later, and Chair was at the Game Developers Conference in California. Parent company Epic Games was there, too, with a show-stopping demo of Unreal Engine 3 running on an iPhone 3GS. "I saw it - it had one little room where you could move around - and thought 'That's pretty cool, I bet in two or three or five years, that's going to be some pretty impressive stuff'."

"I had no idea that three or four months later that I'd be working on Infinity Blade and that the technology was actually there right now," Mustard says.

When the opportunity presented itself to Chair to make an iOS game, Mustard thought about the Kinect demo and "it instantly just clicked for our team. This is an even better way to make Infinity Blade. Because of the touchscreen, you can have that one-to-one feeling of slashing a sword. We thought it was perfect and instantly went into production making Infinity Blade."

Infinity Blade

The game's development was a roller coaster ride. "We'd never made a game so fast. We made Infinity Blade in five and a half months," Mustard reveals. "It was like running at a brick wall at a thousand miles an hour and there wasn't a lot of time for second guessing anything."

Luckily, things fell into place organically.

Take the generations idea, for instance - that defining Infinity Blade gimmick of heroes being replaced by vengeful offspring upon death. "That was something that always inherent in the fiction," Mustard says.

"The expression of it in the bloodlines was just one of those happy coincidences where he had this fictional element but it worked with the gameplay and worked with the constraints of the time frame in which we were making the game. "

"As we were sitting thinking of how the gameplay would flow and how it would loop, we were like 'oh, man, it ties in so perfectly with the fiction,' and we went with it."

While all this was going on, developers from Epic and Chair were also working on Epic Citadel. That "really was a tech demo, and a proof of concept on Epic's part to show that the technology actually worked." To show that "the engine is capable of pushing these polygons and doing this stuff".

Epic Citadel - Download it here for free

It was released immediately after Apple's September 2010 keynote on the iPod touch ended, to prove to iOS owners that their devices really were capable of running Project Sword - the code name for Infinity Blade - which was revealed at the same conference. A year later, and Infinity Blade 2 had a starring role at the unveiling of the iPhone 4S.

"We are so grateful to Apple for its support and for allowing us to be part of not one but two of its keynotes," Mustard says.

"Apple really is looking to always show how amazing and powerful these devices really are, and there is no better way to show that than with Unreal Engine 3 running on one of its mobile devices," Mustard remarks. "It's a great marriage."

Donald Mustard - Chair's co-founder and creative director on the Infinity Blade series - is proud of the game. Thinking back to its hurried development, he says, "we thought we had something really fun and unique, but we had no idea if it was the right thing, if the game was too hard or too easy or too long or too short. We didn't know any of that. I think given all those constraints and considerations, the game was amazing."

Infinity Blade 2

Gamers, it seemed, agreed. Earnings from the game exceeded $10 million in the first six months of release, and was potentially the fastest game to do a million dollars worth of sales on the App Store. It spawned a few DLC packs, an arcade cabinet, a tie-in novelisation, and a sequel - which is out now.

Our review of Infinity Blade 2 should be up on the site shortly.