The game itself has a lot of interconnected systems running underneath its surface, requiring players to actually think in relatively real-world terms about how best to infect the planet. Part of Plague Inc.'s appeal has to do with figuring out how to best exploit these systems. Keeping things spoiler-free, I asked Vaughan to talk about some of the factors he hopes players will pay attention to while playing. "I hope that players think about how their plague would be perceived by the world. Are people likely to notice (or care) if 100 million people in Africa have a cough? Probably not," he said. "What about if one hundred thousand people in the US suddenly go insane and drop dead?" "A key part of the game is deciding how to evolve your disease so that it spreads to as many people as possible and then kills them before they are able to develop a cure," he said. "I spent a long time balancing when a country would first notice a disease or when the world would begin to panic about the plague. It is a fine line to balance to but I am moderately happy with the result." That said, Vaughan discovered something interesting about the plausibility of global infection during his research and development of Plague Inc.'s underlying systems. "I am pleased to report that development of Plague Inc. has led me to be fairly confident that it is impossible for humanity to be completely wiped out by any single pathogen," he said. "I started off with one hundred percent accurately modeled disease spreading / infection algorithms (R0 etc.) and the player (disease) could never win. The game as it stands today has a significant and unscientific bias against humanity." Plague Inc. is conceptually similar to a series of browser-based titles, Pandemic and Pandemic 2, which also task the player with dominating the globe by evolving a contagious and lethal disease. Pandemic 2 even saw an iOS release around the same time that Plague Inc. hit iTunes, but in the case of Vaughan's game, it really seems like there's a lot more going on under the surface than is true in the title that inspired it. I asked Vaughan about the game's development, and what he did to improve upon the idea that inspired it. "I'm a huge fan of the concept behind the web game Pandemic 2 but always wanted more from it," Vaughan said. "One day, I started thinking about what would make the ultimate game in the genre. I ended up with a huge list of ideas: deeper strategy, more options, compelling narrative and more realistic models. In my head, the game was awesome and I really, really wanted to play it. There was nothing remotely like it on the iPhone and I knew I had to make it happen." But what are some of the new things Plague Inc. brings to the idea of playing as a disease? Vaughan cites things like random disease mutations, poppable "DNA bubbles" that appear in newly infected countries, and in-game story events presented via a news ticker--some of which actually require the player to think on the fly and adapt their sickness accordingly. "Story events like the 'iCure' require players to react to the world in order to get the best outcome," he explained. Plague Inc. contains a number of disgusting, real-world symptoms the player's disease can evolve, but everything in the game is viewed from a distance. I asked Vaughan if it was a deliberate decision to not include graphic imagery in the game--which makes it easier for the player to be dispassionate and strategic about the carnage he's causing--or if the presentational choices had more to do with practical reasons about being a team of one. "Ease of development was certainly a key factor," said Vaughan. "I had to be on constant guard against scope creep and only focus on the true essential areas. There is also a style element. I do not think random bits of graphic imagery would be in keeping with the broader theme of the game. I quite like the clean, dispassionate 'DEFCON' feel, as it lets the player act on a truly global scale without getting bogged down in the details. Plague Inc. is an intelligent strategy game and graphic violence would mis-sell it." Other design considerations were made as well. Those who have played Plague Inc. have probably noticed that a handful of geographic borders have been consolidated. I asked Vaughan to touch on why this is the case. "Alaska, Ireland, Portugal and Holland have been the most contentious countries/regions that I had to merge," he said. "Of course, absolutely no offense was intended; they were indeed made for the sake of gameplay." He further explained that some of the border-consolidation had to do with making sure that each "country" could be easily seen and selected on the world map. "Some areas of land would be too small on their own," he said. Another related practical consideration for merging certain borders has to do with how the infection appears to spread. "If part of the country is separate to the other (e.g. Alaska), then it looks very odd and can appear to get infected spontaneously." Vaughan added, "I do hope to add more countries into the game in the future but the only way that Alaska will escape Canada is if it becomes its own 'country' and I don't think this would be good either." The final product is an elegant, menu-driven experience that allows players to focus solely on the evolution and transmission of their personalized disease and relevant statistical information. Sound also plays a supporting role to help beef up the game's ambiance. The evolution of certain systems and world events often translate into subtle background audio queues that help dynamically enhance the game's mood. "To get the sound effects, I worked with a guy called Joshua in the U.S.," said Vaughan. "I gave him a list of the effects that I wanted and he produced some fantastic ones! Each sound effect has a number of triggers and conditions so yes, they absolutely do tie in with the gameplay." Though by any measure, Plague Inc. has already been a resounding success, Vaughan has some interesting plans for updates in the future. Feedback from fans is playing a critical role in the development of said updates. "Fan feedback has been brilliant and we have responded to each of the tens of thousands of emails that we have got," Vaughan said. "It helps me prioritize various tasks and also provides new ideas to add to my 'cool things' list." The next update (1.3) "will add a new plague type to master, bring new world events, let you see the impact of an evolution before you evolve it and play your own music whilst playing. It will also have a load of smaller tweaks and functionality enhancements." A number of fans have also requested some sort of multiplayer functionality, and though it'd be a pretty large development undertaking, Vaughan is receptive to the idea. "There are some really exciting ideas I have for multiplayer in the Plague Inc. universe," he confirmed. "It will be complicated to do properly so it is not my immediate priority but definitely something I would like to look at in the future." Plague Inc. is currently available on iTunes for $0.99, and I personally recommend that strategy game fans give it a shot. An Android version of the game is also in the works, which Vaughan describes as a "key priority." Ndemic Creations will reveal more news about the Android version "very soon!"
Will you be able to destroy the world?