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Sonic Unleashed, known in Japan as Sonic World Adventure, is a 3D action-adventure platformer developed by Sonic Team (Company) (along with Dimps for the Wii and PS2 versions) and published by Sega (Company) for the Xbox 360 (Platform), PlayStation 3 (Platform), Wii (Platform), and PlayStation 2 (Platform) (outside of Japan) on November-December 2008, with the 360 and PS3 version released in Japan on February 19, 2009.
Part of the Sonic the Hedgehog (Franchise) series, and a successor to the 2006 game Sonic the Hedgehog, Sonic Unleashed features a singular campaign combining high-speed platforming levels with slower-paced combat levels, the latter making use of the game's unique transformation for the eponymous hero (where due to an affliction, he turns into a "Werehog" at night).
The game's story takes place after an attempt at foiling Doctor Eggman's plans causes Sonic to lose the power of his Chaos Emeralds, which Eggman then uses to break open the planet's core to unleash a powerful beast (whose revelation has the side-effect of transforming Sonic into a wolf-like beast at certain times of day). Together with a mysterious amnesiac creature he names "Chip", Sonic must travel throughout the world to find special "Gaia Temples", restore the power of the Emeralds, and restore the planet back to normal.
Both 360/PS3 and Wii/PS2 versions of the game have significant differences, with the former version featuring explorable hub worlds, lengthier Werehog levels, and a "Ring Boost" system, and the latter using a menu-based system, more numerous Werehog levels, and a segmented boosting system. The Wii version also makes use of motion controls, particularly for the Werehog levels. Digital 360 and PS3 versions were later delisted in the early 2010's, but were re-released in the late 2010's.
Like Sonic Adventure (Game) and Sonic the Hedgehog, Unleashed is broken up between two specific modes: Towns and Action Stages. Towns advance the game's storyline and house NPC characters (which offer side missions or items to Sonic) and generally lead the player to access the next level (an Action Stage) via that town's "Gaia Gate". In the PS3/360 Sonic Unleashed, new stages are accessed by collecting Sun and Moon Medals hidden within stages and towns, whereas in Sonic Unleashed for PS2/Wii, Sun and Moon medals are awarded strictly by completing stages. In comparison to past Sonic games, the towns in Sonic Unleashed for PS3/360 are considerably more compact in size and generally can be navigated from end to end in a matter of seconds. However, the Gaia Gates in the PS3/360 Sonic Unleashed, while compact in size, can be immensely confusing to navigate while also being unclear in presenting the player with their next objective to progress through the game.
The Action/Town stage motif is further broken down by what time of day they're accessed. While the sun is out, players are given control of Sonic the Hedgehog, who is equipped with the ability to boost, drift, homing attack, leg stomp, wall kick, and quick-step (a strafing maneuver). Once the sun sets and day turns to night, Sonic transforms into The Werehog, a shaggy beast who uses his claws to attack enemies and long stretchy arms for platforming. After defeating a certain number of enemies and charging up enough energy, the Werehog can "Unleash", making him move faster and hit harder, in addition to being invincible.
In Sonic Unleashed for PS3/360, things like defeating enemies, eating food, and completing certain side missions will earn Sonic experience points that he can use to upgrade his abilities. For Sonic the Hedgehog, Speed and Ring Energy can be upgraded, and for the Werehog, Strength, Combat, Health, Shield, and Unleash can be upgraded, and although the Werehog starts the game with only a small handful of attacks, by upgrading the "Combat" ability, over 30 combo attacks in total can eventually become available for the player to choose from. (In Sonic Unleashed for PS2/Wii, the amount of combo attacks available is much fewer.)
The game of Sonic Unleashed spans up to 9 distinct continents. But not all continents are available all of the time -- frequently the player will have to return to locations at specific times of day in order to progress forward in the game. For example, while the player visits the continent of Adabat during the night as the Werehog, they do not return there as Sonic in the day time until some time later.
Each continent featured in Sonic Unleashed generally has one town hub, one Gaia Gate hub, one main daytime stage act, and up to 4 main nighttime Werehog stage acts. In addition to those, a continent can have one or more more boss encounter (as either Sonic or Werehog), and any number of optional mini-acts to complete. (In Sonic Unleashed for PS2 / Wii, these additional acts are sometimes as long as the main stage.)
Note that Sonic Unleashed for PS3 / 360 also includes two Tornado shooting stages, which do not take place on any continent.
Tomoya Ohtani (Person), one of the soundtrack artists from Sonic the Hedgehog and Sonic Rush Adventure (Game) returns as lead composer on the soundtrack for this game along with Sonic musical veterans Kenichi Tokoi (Person), Fumie Kumatani (Person), Hideaki Kobayashi, Takahito Eguchi (Person), and Mariko Nanba (Person). Orchestrated tracks for the game were performed by the Tokyo Philharmonic Orchestra. The game contains two vocal tracks:
Purported to be in development since 2005, Sonic Unleashed's "Hedgehog Engine" is a multi-purpose game engine developed by Sega as an alternative to engines like Unreal Engine 3 (Concept), idTech5 and the Source Engine (Concept). At the time of its release, the Hedgehog Engine was most notable for two relatively cutting-edge features: the rapid speed in which it could load streamed texture data off of the disc (eliminating texture pop-in), and its ability to render Global Illumination lighting data.
Global Illumination is a term used to reference the act of light bouncing off of surfaces. For example, if sunlight streams in through an open window on to a green floor, green light will bounce outwards from that surface and cast the entire room in that color. Hedgehog Engine was one of the first game engines to display this type of lighting technology.
At the time of release, calculating pre-baked Global Illumination data for a single level in Sonic Unleashed would take a networked render farm of 100 computers an average of 2-3 days.
Although Sonic Unleashed was released on four different platforms, two different versions of the game exist: the "High-Def" version for the Xbox 360 and Playstation 3, developed by Sonic Team, and the "Standard-Def" version for the Playstation 2 and Nintendo Wii, co-developed by Dimps Corporation (Company). Both versions of the game follow roughly the same story, but feature significant differences:
Near the launch of Sonic Unleashed, Sega celebrated the launch of "Sega Sammy Visual Entertainment", an animation studio opened not only to create high-quality CGI for Sega games, but to produce feature-length movies. In addition to animating all of the CGI for Sonic Unleashed, Sega Sammy V.E. produced an 11 minute short film titled "SONIC: NIGHT OF THE WEREHOG". In it, Sonic and Chip are caught in a rainstorm and take shelter in what looks to be an old abandoned mansion.
Unknown to them, a trio of ghosts haunt its halls - two of the specters are armed with cameras and compete for the affection of a lady ghost by snapping photos of their victim's frightened expressions, which she finds amusing. Though Chip is easily scared and makes for easy pickings by the ghosts, as they move in and attempt to scare Sonic, the ghosts are surprised when the storm breaks to reveal a full moon - causing Sonic to transform in to the snarling Werehog. Undeterred, their efforts to humiliate Sonic eventually devolve in to a knock-down drag out fight for supremacy. The two photographer ghosts from Night of the Werehog actually make cameo appearances in Sonic Unleashed, in the side-missions "Tower Terror" and "Fright Fight". In 2010, "Sega Sammy Visual Entertainment" was renamed to "Marza Animation Planet", where they underwent their first feature-length movie project: a CGI adaptation of the anime "Space Pirate Captain Harlock".