Sonic the Hedgehog 4: Episode I

Sonic the Hedgehog 4: Episode I (ソニック・ザ・ヘッジホッグ4 エピソードI Sonikku za Hejjihoggu Fō: Episōdo Wan?), originally codenamed Project Needlemouse, is the first part of an episodic video game in development as part of the Sonic the Hedgehog series. This episode was released in October 2010; it was originally to be released in the summer of 2010 but was pushed back for further development. The game was first announced on 8 September 2009, and its real name was revealed on 4 February 2010.

The game is a 2.5D side-scrolling platformer reminiscent of the original Sonic games, with an emphasis on speed. It is playable in high definition. For Episode I, the iPod Touch/iPhone version was released on 8 October, the Wiiware version was released on October 11, the PSN version was released 12 October and the XBL version was released 13 October. On 19 January 2012, Sonic 4 was released for the PC on Steam. A direct-follow up, Sonic the Hedgehog 4: Episode II, was released on 2012.

Story[]

Sometime after Sonic the Hedgehog 3 & Knuckles, with the Death Egg finally destroyed and the Master Emerald safe, Sonic parts with Tails, Knuckles and Sally to explore new territories on his own. Meanwhile, a vengeful Dr. Eggman has taken measures to defeat his arch-nemesis by enhancing his past creations and mechs.

Despite Dr. Eggman's best efforts, Sonic destroys each of his refined creations and chases the madman to his newest lair, the E.G.G. Station Zone. There, Sonic defeats each of his creations once again, including the powered-up Death Egg Robot, which destroys the station. Safely back on his planet, Sonic, Tails, Knuckles and Sally celebrates his victory in Splash Hill with his animal friends.

A post-credits scene, obtained by collecting all the Chaos Emeralds, shows Dr. Eggman laughing, along with the silhouette of Metal Sonic, leaving a cliffhanger for the next episode.