Everybody knows the story of Angry Birds.
A slow starter, the original game in the franchise was Rovio's 52nd crack of the whip and, eventually, proved to be the game that made the Finnish studio its millions.
It may have since been surpassed by the likes of Candy Crush Saga and Clash of Clans when it comes to pure revenue, but Angry Birds as a franchise remains a mobile behemoth – arguably the biggest IP in the smartphone era.
As a result, Rovio doesn't hand over the keys to its mighty empire lightly, making the firm's decision to hand the reins to UK-based Exient for the development of Angry Birds Go – the franchise's first attempt at a kart racer – something of an accolade in its own right.
Everybody's heard about the bird
Exient was founded by Dave Hawkins back in 2000, with an aim of re-imagining IP for various clients on handheld. Little over a decade later, however, Hawkins re-purposed the company to focus on the mobile free-to-play scene.
In view of this shift, Rovio approached Exient to take its beloved franchise in a new direction, and Graeme Monk – the firm's studio director - was ready for the challenge.
"Angry Birds itself has become a worldwide phenomenon and we were given the enviable opportunity not only to present Angry Birds in a different universe and format but also to work with Rovio in exploring the free-to-play market," says Monk.
"In addition to this, we also worked very closely with Hasbro and the firm's Telepods technology to create a product that not only exists in the mobile space but as a physical product."
The companies decided the karting genre was a good fit due to simple supply and demand - there were calls on various forums for a mobile karting game and Rovio believed Exient was the one to deliver.
"The trick was in trying to provide something that took the genre to new graphical levels, incorporated the Angry Birds IP, was also simple to play, easy to control and appealed to a much wider audience," says Monk.
"We developed a prototype that experimented with a number of control mechanics and iterated the experience from there. Once we had something that felt good to play it proved that you could take a challenging genre and release it for a touch device."
Although Exient had never worked on a karting game specifically, it had, however, worked on a wealth of racing games, from Need For Speed to NASCAR.
"There was an immense amount of research into other karting games to drill down into what was fun about the experience," recalls Monk. "Once we had that, and a great mechanic on which to base it, we could build our own vision of a what an Angry Birds karting game would look like."
Obviously, one of the things that makes the likes of genre figurehead Mario Kart appealing to the masses is what could be dubbed the game's 'social element' (read: firing a blue shell up a friend's backside). Angry Birds Go currently lacks such a facet, but the team is passionate about adding such a vital component via an update.
"Multiplayer was something we focused on from the very beginning, but was held back so we could gain feedback from the market as to what type of multiplayer was desired," reveals Monk.
Multiplayer was held back so we could gain feedback from the market.Graeme Monk
"As with most free-to-play games, there is a level of servicing the live product once it's been launched and allows us to tailor the experience to what the players actually want, not what we as developers believe they want. This is one of the real strengths of the free-to-play market: allowing us focus our talent and efforts into significant features that is driven by user feedback."
It's not all strengths, however. The public perception of free-to-play is shifting - the ethics of the model frequently brought into sharp focus. With a game like Angry Birds Go - cutesy visuals and its Hasbro-manufactured toy range in check – accusations that Rovio and Exient alike are directly targeting a free-to-play game at kids is rife. According to Monk, however, this just isn't the case.
"Most games try to appeal to as wide a market as possible," suggests Monk. "The visual design was inspired and heavily influence by previous Angry Birds titles as wells as the Angry Birds Toons series. Obviously, both of these exist in a 2D realm which allowed us to play quite heavily with 3D, lighting, shaders, visual effects and the like.
"We feel that the end result is not focused just at young children but has a wide appeal, just as the original products had and continue to do so. The numbers actually back this up, since most of the fans of Rovio games are in their 20s or 30s, or older."
Such a balanced approach means Monk's not worried about the public perception (and increasing press coverage) of children spending out on in-app purchases.
"It appeals to children just as much as it appeals to the inner child inside everyone," says Monk. "We worked very closely with Nicholas Lovell who has a vast amount of experience within the free-to-play market - Nicholas' Gamesbrief blog is an excellent place to get a better understanding of what free-to-play is all about.
"A core aim was to provide a compelling, fun experience that didn't have to be paid for if the player didn't want to. All products need to monetise in one way or another - and free-to-play is no different. We endeavoured to develop Angry Birds Go as an experience that didn't have paywalls but was a sensible balance between what character the player chose to race with and their time within the game.
"Did we get this right? Not in the very beginning, and this is something that we are continually evolving. Probably the most controversial aspect of this is the bird energy mechanic. We can honestly say that this was not designed as a time sink to get people to pay, but to encourage players to switch to a different character and to try them all out; every character has a subtle difference in how it races.
"We still stand by one of the core pillars in the game's design: to provide a compelling, free-to-play experience that the player wouldn't have to pay money for. It is, remains, and will be a game in which every race and every challenge can be completed without ever having to spend a single penny."
Such is the status of the Angry Birds IP that any faults were likely to jumped on by critics – it's fair to say Angry Birds Go didn't get the easiest ride in terms of reviews – but it's Monk's position that the energy system was a result of trying to encourage players to try the full roster of characters.
Those characters, all subtly unique in their handling, all survived the game's shift from 2D to 3D during development with their personalities intact.
"The characters themselves are strong enough that they can be used in different formats and genres," agrees Monk.
"The challenge was how can we use their character traits within the a racing game and how could they be portrayed. We managed to achieve this with the creation of the bird and pig abilities which replaced the weapons more traditionally utilised in racers. Thus we managed to keep the same style of gameplay and still kept it within the Angry Birds universe."
It wasn't just about portraying the character's traits through mechanics, either. The transition to 3D meant thinking about the birds' visual design from a whole other dimension.
With free-to-play games, players spend as much time in the actual game as they do in the design of the user interface.Graeme Monk
"Characters within a 2D world generally have aspects of the character filled in subconsciously by the viewer: things that we take everyday for granted such as lighting, behaviour, how characters move and emphasise," says Monk. "In addition to this, the environment and world in which the birds live literally takes on another dimension.
"The artistic vision was developed with 3D in mind - an understanding that what was 2D would appear in 3D not only in individual form but also within the world. The design concepts played heavily within Piggy Island and scenic features of the island. This in turn influenced key aspects of the tracks and how they appeared within the game.
"Sound design in turn needed to be focused on the birds themselves rather than karts, especially as the karts didn't have engines. The birds and pigs needed to come across and fun but competitive racers in an environment devoid of modern day contraptions. The addition of a vibrant Euro-pop soundtrack by Pepe Deluxé added to the sense of fun within the game."
To achieve its initial vision of transferring Angry Birds into a new plane – and with the mechanics and visual direction both settled on - Exient worked for four months to get the prototype ready.
In all, Exient spent a further 15 months producing karts, tracks, environments, effects and the abilities of the individual characters. At the peak of development, there were 40 people working on the title, with Rovio also drafting in character designers, producers, QA testers and game designers.
"Exient has its own proprietary technology, XGS, that has been developed over the last ten years or so," says Monk. "This was the core engine of the game and allows us to develop across many platforms simultaneously. 3DS Max was used for a majority of the creation of the in game art along side XGS plugins allowing us to use post processing techniques such as shaders. And coffee - that was a great tool and helped with some late nights."
Exient settled on the game's control scheme during that four month prototyping stage. The aim was to keep it as simple as possible, to appeal to the widest audience.
"We started out with something which was analogue to a more console experience, having acceleration, braking, drifting, boosting and weapons all confined to a touch interface," recalls Monk. "We played around with virtual joysticks, contextual touch and various other schemes before paring the controls down one by one into much simpler mechanic designed around just steering and the bird abilities."
Although said control scheme made things easier for the player, it also presented its own set of challenges when designing the game.
"The simplicity of the controls meant that we needed to rely on other aspects of the game to handle things such as acceleration and braking," remembers Monk. "The decision to go with a downhill world was inspired and allowed us to handle these additional aspects within the world itself - acceleration could be controlled by gravity, braking and handling by the design of the track.
"This presented a further challenge for our track designers, to design something that was not only fun and challenging but allowed us handle these aspects invisibly across a multitude of different racing styles: straight forward racing, stunt, air, off road and some styles yet to be announced."
This wasn't the only challenge Exient faced, however. The team also wanted the UI to be super slick, and it underwent a multitude of iterations before the final approach was settled on.
"Another major challenge was the interface and menu systems," says Monk. "With free-to-play games, players spend as much time in the actual game as they do in the design of the user interface. The UI was designed, redesigned, designed further, thrown away and started again. The final UI is something like the fourth redesign and something that is still being tweaked and adjusted to make the experience more fun and compelling."
The UI and the control scheme are the only aspects that have undergone a radical change, however - other than in the planning stages, where a 2D karting game was on the cards. This idea was thrown aside once the prototype was created.
Of course, with a free-to-play game, the work never really stops. Monk says Exient is still hard at work on Angry Birds Go, responding to the mountains of feedback.
Another challenge of creating a free-to-play game, though, is that work is never really finished. Exient is still working on the game and responding to feedback, with the aforementioned multiplayer mode inbound. Said changes are designed to ensure Angry Birds Go lives up to the precedent set by the original releases in the franchise, with building on the game's existing base now key to its longterm success.
As we all know, keeping up momentum -even when you've been fired from a catapult - is often easier said than done.