of both sets of Emeralds, as Sonic and Blaze promise to one day meet again. As Sonic and Tails set sail, Marine appears on her new boat, thanking Sonic and Tails and promising she will study to become a captain. The three say their final goodbyes as Sonic and Tails fly off for home. Development and release Like its predecessor, Sonic Rush Adventure was developed by Dimps with assistance from Sonic Team for the Nintendo DS. It was developed alongside Sonic Rivals 2 for the PlayStation Portable. As the developers began to work on the project, director Sakae Osumi, inspired by adventure novels, television programs, and films, decided that the sequel should be set on the high seas. As the original Rush centered around Blaze coming to Sonic's world, the writers decided to make the sequel center around Sonic and Tails becoming stranded in Blaze's world. Wondering who would meet the two first in this dimension and what would inspire their adventure, the designers created the character Marine. They also chose to give her an Australian accent, to make her have a sense of being loud and active. The developers also created the nefarious pirates, who serve as primary antagonists. In programming the game, the team used the same underlying technology used to create Sonic Rush. However, the developers enhanced the presentation, including a dynamic camera system and 3D elements in gameplay, most notably in boss fights. The game also makes greater use of the DS's touchscreen, featuring sea-travel minigames using the touchscreen, in addition to a new tutorial system. The musical score of Sonic Rush Adventure was composed by Tomoya Ohtani, Seirou Okamoto, and Mariko Nanba. The sound director was Teruhiko Nakagawa, who recruited the voice actors and made all the sound effects. The composers sought to preserve the style of music present in the original Rush while adapting to the game's theme of adventure; it also features elements of tropical and hip hop music. Sega first announced Sonic Rush Adventure on April 16, 2007, and revealed more information about it the following month. A demo version was playable at the Electronic Entertainment Expo (E3) in July 2007. Sonic Rush Adventure was first released in Europe on September 13, 2007, followed by North America on September 18, Australia on September 27, and Japan on October 18. It was released in South Korea on September 17, 2009. Sega published the