Story
Sonic Unleashed begins at the end of an untold story which sees Sonic confronting his nemesis, Doctor Eggman, bounding around a fleet of spaceships, and transforming to Super Sonic - Sonic transformed using the power of the Chaos Emeralds - in order to stop him.[7] However, Eggman manages to trap him using a powerful new ray weapon[6] which corrupts the power of the emeralds.[7] He then uses the Emeralds' energy to unleash a powerful beast from the center of the planet[11], which has devastating consequences, shattering the planet into pieces; it is up to Sonic to solve the crisis by travelling the world, finding shrines that will fix the Emeralds, in order to return the world back
to normal.[7]
In addition, Eggman's ray also causes an unexpected transformation to Sonic's state, [6] and Sonic's progress will be made even more difficult when the ray and the transformed Emeralds have the unforeseen
side-effect of transforming him into a werehog[12] - a beast form with greater strength and abilities - at night.[6][13] Characters
While the following characters have been confirmed to appear in the game, Sonic is the only playable character during the
main action stages.[4][7] However, mini-games are available, during which time one other character will be used in order to complete them.[7][13]
Gameplay
Third-person gameplay in the
Mykonos level.
Gameplay will primarily consist of two modes: 2D side-scrolling platform gameplay, rendered with 3D visuals (as found in
the Sonic Rush and Sonic Rivals series), with seamless shifts to behind-the-back, third-person stages.[6] Concepts returning from past games include Sonic's trademark high-speed gameplay, as well as improved lock-on for automatically
targeting and hitting enemies.[3] Sliding across the ground also returns, and a new feature, Speed Drift allows Sonic to slide around a corner
at high speed. Players will also be able to perform a new side-step maneuver known as Quick Step,[6] allowing Sonic to instantly dodge obstacles to the left or right. As the player goes through the game, and Sonic gains
more experience points, Sonic will be able to upgrade to gain new abilities.[5]
An on-screen Ring Energy meter can be filled by collecting rings, which is used to activate a temporary speed increase
known as Sonic Boost, during which time the camera uses a fish-eye effect and motion blur; hitting enemies and obstacles
will reduce the meter.[8] Action Chaining allows the player to collect energy more quickly, by collecting rings faster[14] or by stringing together sets of actions, including button input sequences, some of which will be in midair.[4] Repeated action chains will allow the player to perform special moves or access different routes in the level.[4]
Side-scrolling gameplay in Sonic Unleashed.
During night sections of the game, Sonic transforms to his alternate Werehog form, and gameplay will shift from fast-paced
action to a slower, more platform-oriented style of gameplay.[12] The Werehog form allows Sonic a great deal of strength, and gameplay involves smashing enemies and destructable environments,
whilst his stretchy arms will allow him to reach high platforms and perform special attacks. [12] The Ring Energy meter changes to two bars, Shield and Vitality.[12]
Levels
Nine lels exist in the game, all of which are based on real-world locations.[7] Those levels whose order is known include the first level of the game, Mykonos[5] - initially generically dubbed "Greece"[3] due to its design being based on the country - which will be used to initiate the player into some of the game mechanics,
as well as provide a sense of speed.[5] The fourth level is one based on Europe.[5]
Further levels include those seen in screenshots, such as a sandy, desert-like level set in Africa,[7] and those that have been previewed by journalists. These include China, which includes a run along the Great Wall,[7] a Spanish villa,[7] and a level based on New York City,[7] where Sonic was shown to run between skyscrapers.[15] Levels will have multiple pathways for players to follow.[6]
Levels have been designed so that the two aforementioned modes of 2D and 3D gameplay will be switched between roughly every
fifteen to thirty seconds, whilst no stage will last for more than five minutes.[7] In addition, the game features a day-and-night system; some parts of the action stages have been built such that time
will pass, and these can be played as either Sonic or his werewolf form, whilst others are only built for one specific form,
and during these areas, time will not pass.[13] The player will easily be able to advance time manually during the areas allowing either form, should they prefer one
or the other.[13]
The game will also feature town stages, or "hub-worlds", that are set in the same environments as the action stages,[7] and players will be able to walk around the environment freely and speak to townspeople; however, this "overworld"
can be completely ignored, should the player prefer to simply play through all the stages.[8] Optional side-quests will also be available from these stages[8] - the only time characters other than Sonic will be playable[7] - whilst players will be able to gain various extra items by talking to different townspeople.[4]
Development
Sonic transforming into his Werehog form.
The development of Sonic Unleashed was announced in April 2008. Unleashed was originally intended to be the
third installment of the Sonic Adventure series[16] and subsequently, at an early development stage, had the working title Sonic World Adventure, complete
with work-in-progress logo. However, the development team began to introduce enough new innovations to separate it from the
Sonic Adventure titles,[4] and so a new title, Sonic Unleashed, was decided upon.[17] It was then later revealed that the game's name in Japan would in fact remain Sonic World Adventure for its release
there.[7]
The game is currently being developed internally by Sonic Team.[18] It will be a multiplatform release on the Wii, PlayStation 3, Xbox 360, and the PlayStation 2.[1] There are two development "silos" that work on two separate builds of the game: one for the Xbox 360 and PlayStation
3 version, and one for the Wii and PlayStation 2 version.[5] The Xbox 360 and PlayStation 3 versions will run on Sega's "Hedgehog Engine", which has been in production for three years[1] and will produce a frame rate of 30 frames per second.[8] The Wii and PlayStation 2 versions will not take advantage of the Hedgehog Engine, instead using a modified version
of an existing, internal Sega engine.[4]
The Wii version of the game will be developed specifically to take advantage of its controller's capabilities, with notable
differences in gameplay. The game will use the Wii Remote and/or Nunchuk option; whilst character movement and basic actions
will be assigned to buttons, certain actions will benefit from physical movements.[4] It will support the GameCube controller, and also the option of using the Classic Controller. The levels, whilst sharing
the same styles, themes and motifs as the Xbox 360 and PlayStation 3 versions, will be different to those shared between the
Wii[4][19] and the PlayStation 2 versions,[5] and Dimps will only be involved with design of the daytime stages for these versions.[3]
Initially, it was stated that Unleashed was to be intended solely as a single-player experience, and would not offer any
multiplayer or online modes.[4] However, more recently, references to online modes have been alluded to.[12] A demo will be available on the PlayStation Store and on Xbox Live near to the game's release.[13]
