In a postmortem of PlayStation 3 co-operative game ibb and obb, designers Richard Boeser and Roland IJzermans gave some great insight into many of the design decisions behind the game. The Sparpweed devs covered a wide range of design elements from the game. For example, Boeser explained that the diamonds that players collect in the game aren't actually in there for score-purposes at all. The game originally had no diamonds to collect when you killed enemies, but the team quickly realized that players simply weren't working together, and were instead running off in separate directions. To combat this, and essentially make people want to work together, diamonds were added to the game. When one player kills an enemy, diamonds fly out from the opposite side for the other player to collect. Therefore, the opposite player now wants to follow along and work as a team. Score elements were thrown in later as a secondary element. "We do show points at the end of the level, but the real reason they're there is to encourage co-operation," added Boeser. "And if I've learnt one thing from making this game, it's that people love picking up shiny things."

No capitals

ibb and obb is spelt without capital letters -- and there's an important reason for this. "This turned out to be one of the most difficult features of the game," said Boeser. The story goes that the game was originally called Brothers, but the team didn't like that this title as it essentially explained the story behind who these two characters were. The names ibb and obb were taken from a book by Jasper Fforde called The Well of Lost Plots, in which two generic characters are given these exact names, and not given capital letters until they had evolved as characters. They essentially had to earn the capital letters. "This was a super nice analogy for us," Boeser noted. It also meant that anyone could relate to the characters of ibb and obb, whether it be two kids, a father and son, or whoever else plays the game.

Should ibb and obb have single player?

A big sticking point for the Sparpweed team has been the single player. While they found themselves enjoying it during development, when the game was actually released, reviewers and players weren't so kind. "When we started this game, we only showed the co-operative side," explained IJzermans. "We thought, we do need to include a single player. You need something to do by yourself." While the team was designing the game, they did quick tests by controlling each character on each of the PS3 controller sticks. They came to enjoy playing the game this way, and decided players would enjoy it too. The original idea was to include the single player as a bonus mode, and focus more on the co-op play -- but when it came to designing the minimalistic menu system, they simply opted to stick "single player" right underneath the main two player mode. "We perceived it as a crazy bonus mode," says IJzermans -- but unfortunately players and the press didn't see it that way. Even worse was that people outside of the development team found the single player incredibly difficult and not much fun. "It's awful," the dev admitted. "It's made us question, why did we put it in there? A lot of reviewers bashed the single player - and they were right." If they went back, would they remove it? Leaving it out would have been a statement, the team reasoned, but then again some people actually said that they found they'd play some of the single player, and then move onto the co-op as a result of having fun. The team still isn't sure what they'd do in hindsight.

The color approach

The way in which the Sparpweed team tackled the color scheme and design in ibb and obb is particularly notable. All the backdrops and decorations in the game are modelled around a grey-scale color scheme only. The decoration itself doesn't hold any color information, and instead pulls its colors from set schemes outside of the game. To better explain this, the pair took a photo of the GDC Europe audience, and then placed these colors directly into a color scheme. The game was then able to pull the color information directly from this photo and populate the world with the audience colors. This was all done in roughly a minute. Essentially, it means that the team can very easily chop and change the game's color scheme on the fly, and easily make colors blend into each other as player's progress through the game.