larger environments than Echoes. The developers were also interested in using the WiiConnect24 feature to provide additional content for the game that would be accessible from the Internet. Retro announced that Corruption would be the final chapter of the Prime series and would have a plot "about closure, told against the backdrop of an epic struggle". After the Wii Remote was revealed, Nintendo demonstrated how Metroid Prime 3 would take advantage of the controller's special abilities with a version of Echoes modified for the Wii and shown at the Tokyo Game Show in 2005. Originally envisioned as a launch game for the Wii in November 2006, Corruption suffered many delays, but eventually being released in August 2007 generally positive reviews, and over 1.60 million copies sold worldwide. While Retro was busy with the Prime sequels, they had to pass on the Nintendo DS game Metroid Prime Hunters. The eventual developer, Nintendo Software Technology (NST), worked closely with Retro to design the game's art and characters to make sure that they fit into the overall Metroid series. 2010–present: Donkey Kong Country series, Metroid Prime 4, and other projects In April 2008, Retro saw the departure of three key developers, designer Mark Pacini, art director Todd Keller, and principal technology engineer Jack Mathews, who went on to form their own company, Armature Studio. Around the same time, Shigeru Miyamoto asked fellow producer Kensuke Tanabe to recommend a studio that could develop a new Donkey Kong game, and Tanabe recommended Retro. Kelbaugh had worked on the Donkey Kong Country series during his years at Nintendo of America, and had interest in continuing with the franchise. Retro accepted the task, and thus started development of Donkey Kong Country Returns. Similar to New Super Mario Bros., the game was developed with the intention to invoke nostalgic feelings in the player with its art style and sound, while trying to provide them with new gameplay experiences. Returns employs fully polygonal 3D graphics with three times the amount of textures and polygons that Corruption offered, and over the course of six months, two thirds of the game's tools and engine had to be rewritten by the programmers. Development accelerated at the outset of 2010, and the project was just "beginning to cohere as a game" around the time of E3, when it was officially announced to the press. Although the game was set for release in autumn