[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/CopyofSonicUnleashed.jpg]]
[[caption-width-right:350: Sonic the Werehog and Sonic the Hedgehog.]]
-->''Sonic is on a race against time to save the world... and himself!''

[[BigBad Mad scientist]] Dr. Eggman has a new plan to TakeOverTheWorld: using the Chaos Emeralds to release a titanic abomination called Dark Gaia [[SealedEvilInACan from its imprisonment]], then building his new empire on the ensuing ruins.

[[YouCantThwartStageOne Eggman is successfully able to capture Sonic, drain the Chaos Emeralds of their negative energy and use them to power]] [[WaveMotionGun a big honking laser beam]] that awakens Dark Gaia and [[WorldSundering shatters the world into seven pieces]]. However, this plan has an unintended side effect: caught at the source of the blast, Sonic is bathed in negative energy and develops an awkward case of [[OurWerebeastsAreDifferent lycanthropy]].

[[CursedWithAwesome Cursed into the form of a "Werehog"]] and cast down to Earth, Sonic must now do what he does best: foil Dr. Eggman by recharging the Chaos Emeralds and putting the world back together one continent at a time. Helping him is Chip, a small critter with amnesia and a mysterious connection to Dark Gaia.

Leaked and then officially announced in early 2008 for the {{Xbox 360}}, {{PlayStation 3}}, {{Wii}}, and {{PlayStation 2}}, ''Sonic Unleashed'' was hoped to be the game that would stab a jolt of life into the stagnated ''Sonic'' franchise, which suffered from hitting the PolygonCeiling hard and had most recently put out the widely-criticized 2006 ''[[VideoGame/SonicTheHedgehog2006 Sonic the Hedgehog]]'' game. Thus, when the Werehog was subsequently leaked and then revealed, InternetBackdraft immediately ensued, with many fans and even professional sites basically screaming "WHAT THE EFF, SONIC TEAM". This carried over to [[ReviewsAreTheGospel many professional reviewers' opinions]], some of whom [[EightPointEight gave the game even lower scores than its widely-panned predecessor.]] In contrast, the fans' general opinion is that Sonic's levels are much more along the lines of what a current-generation ''Sonic'' game should be like; you'd be hard-pressed to find such an opinion on the Werehog.

Oddly, it turned out that ''Unleashed'' was for all intents and purposes two games -- the version released on [=Xbox=] 360 and [=PlayStation 3=] was developed by Sonic Team while the PlayStation 2 and Wii versions were developed by handheld ''Sonic'' developer Dimps. While they all share the same story, similar gameplay mechanics, and level names, the actual design of the levels, as well as the way the player progresses from one to the next, is completely different between the two versions. The Wii and [=PS2=] versions have many more Werehog levels, but to compensate each level is much shorter. There's also a 2D version for mobile phones by {{Gameloft}}.

Released in Japan as ''Sonic World Adventure''.
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!!This game exhibits examples of:
* ActionCommands: This game marked their introduction to the Sonic series. The two Tornado Defense missions are meant to get you used to the button inputs, and there are several points in each level where you input several buttons in a row to perform tricks and reach higher ground. They're also a fast and efficient way to instantly kill enemies in Werehog stages, as well as racking up points in said stages.
* ActionGame: The Werehog controls much like {{Action Game}}s such as ''VideoGame/GodOfWar''.
* AbsentMindedProfessor: Professor Pickle.
* AllThereInTheManual: It's never explained in-game exactly why Sonic transformed into the Werehog, but the instruction manual actually contains some insight into this. It turns out, when Eggman used the Chaos Emeralds to unseal Dark Gaia, Dark Gaia and the Emeralds became linked. Due to Sonic's close proximity to the Emeralds at the time, he absorbed some of Dark Gaia's energy. Since Dark Gaia is shown to only affect people at night, this is why Sonic only transforms when the sun goes down. This also explains why Dark Gaia absorbed some dark energy from Sonic to gain power, removing the Werehog transformation.
* AmusementParkOfDoom: Eggmanland.
* AndYourRewardIsEdible: The Chili Dogs that are obtainable from the Don Fachio Hot Dog Vendors upon successful completion of the missions they offer.
* ArtEvolution: Stemming from complaints about Sonic 06's copious uncanny valley, Unleashed brings a major overhaul to the series' art style, from realistically rendered worlds with cartoon anthropomorphic animals in them, to stylized backgrounds to better match the characters. The humans are a lot more stylized and cartoony than they were in previous games. Sonic himself also got a slight redesign, shortening his limbs and quills to create look bridges the gap between his classic and modern designs.
* AsideGlance: Sonic and Chip both do this at some points.
-->'''Sonic:''' Uh-oh, did I fall on him?
* AsLongAsItSoundsForeign: Pretty obviously with the hubworlds. They're all obvious expies of real-world locations, and their names (and the names of the people in them) sound stereotypical of said locations, yet obviously don't mean anything.
* AttackItsWeakPoint: The goal for boss battles.
* AwardBaitSong: [[http://www.youtube.com/watch?v=n2zJbI0alF8#t=5m19s Dear My Friend]] by Brent Cash
* {{Badass}}: Sonic, in both hedgehog and werehog forms. From phoenixes to [[HumongousMecha super robots]], nothing can stand against him for long.
* BadassMustache:
** Most of the Don Fachio vendors have one, each one unique to the individual vendor.
** [[BigBad Dr. Eggman]] still has it.
* BatmanGambit: Dr. Eggman pulls an epic one against Super Sonic in the intro cutscene. He manipulates Sonic by leading him to the center of his earth shattering cannon and takes out his super form.
* BeehiveBarrier: The Egg Devil Ray is covered by this; only the Sonic Boost can break through.
* BigBadEnsemble: Dr. Eggman and Dark Gaia.
* BigEater:
** Chip. He {{lampshade|Hanging}}s both this and BottomlessBladder: "I get hungry so easily! I wonder where it all goes..."
** In one cutscene, Eggman downs an entire sub sandwich pretty much in the span of being offscreen for about two seconds.
* BigGood: [[spoiler: Light Gaia, AKA Chip.]]
* BigOlEyebrows: Professor Pickle.
* BlockPuzzle: Occurs frequently in the Nighttime stages.
** The entire point of the Shamar boss, Dark Guardian.
* BookEnds: The game starts with the end of one adventure and the beginning of a new one. It ends the exact same way.
* BossBanter: "You little... [[DepartmentOfRedundancyDepartment you little]]!"
* BossOnlyLevel: Savannah Citadel, a full level in the PS360 version, is only used in the Wii and PS2 version for the Egg Beetle boss.
* BreakingTheFourthWall:
** In the Playstation 3/Xbox 360 version of the game, Sonic blatantly looks at the score panel for his overall rank on the end of mission results, and reacts accordingly. He also glances towards the screen a few times in cutscenes.
** He does this in the Playstation 2/Wii version as well. If you play as the Werehog, however, whether he rejoices or turns around and slumps onto the floor in a brief hissyfit depends on your end of stage ranking.
** In the first (or second, if you count the intro) cutscene, when he finds out Chip has amnesia, he basically does this:
--> '''Sonic''': Uh oh.
--> ''(He turns to the camera)''
--> '''Sonic''': Did I fall on him?
* CameraScrew: The camera is actually pretty good at doing its job for the most part, until you reach balance beams, when the camera constantly swings around to get behind Sonic. Impatient players may find themselves suddenly falling off the beam, and, at worst, plummeting to their death.
* CheckPointStarvation: In the HD versions of the game, one mission involves getting to the end of Eggmanland, a NintendoHard stage that indeed is comparable to those of the old 8-bit games--without any usable checkpoints and with a time limit. It is also by far the longest stage in the game, considering the time limit is 45 minutes.
* CitadelCity: Savannah Citadel.
* ClingyJealousGirl: Amy Rose, though very much toned down in comparison to previous games.
* CollisionDamage: Averted. The enemies have to actually attack you to cause damage, with the exception of [[TheSpiny enemies that generate electricity]].
* CombatMedic: The Heal Masters.
* CombatTentacles: Dark Gaia has several of them, not that he uses them during the actual fight.
* ConceptArtGallery: [[GottaCatchThemAll Unlocked piece by piece.]]
* ConsultingMisterPuppet: An NPC, Wentos, in the PS3/360 version of the game, has a Chao puppet that helps him overcome his shyness and generally speaks for him while he is still too shy to interact with others.
* ContinuingIsPainful: As per tradition with most modern Sonic games, dying in a level resets your points, which can be a major blow if you're trying to rank well.
* ContinuityNod:
** In his idle animation (at least in the Wii/Playstation 2 version), Sonic lies down a la ''VideoGame/SonicTheHedgehog2'', and at the start of some levels in the Playstation 3/Xbox 360 version, he stretches his legs a la ''SonicAdvance 2''.
** Also, in the [=Wii/PS2=] version, there's an NPC who compliments Sonic's eyes, then remarks "They don't change color, do they?" Could be a subtle TakeThat against [[FanDumb people who complained about]] [[TheyChangedItNowItSucks Sonic having green eyes]] from ''Sonic Adventure'' onward or merely a lampshading that Sonic's eyes ''do'' change colour - From green in his normal form, to [[RedEyesTakeWarning red]] when he transforms into Super Sonic.
** Three NPC's from the Eggmanland hub world, the EF-[=MD1991=], EF-[=DC1998=], and EF-[=XB2006=], reference the years of release and some of the consoles for [[VideoGame/SonicTheHedgehog Sonic 1]], VideoGame/{{Sonic Adventure}}, and VideoGame/SonicTheHedgehog2006.
* ConvectionSchmonvection: A good portion of Eggmanland takes place over lava, which Sonic seems to have no qualms about standing ten feet over.
* CrateExpectations: There are some here and there, used for pressing switches and hurling at enemies.
* CutSong: The Wii/PS2 version misses out on both Savannah Citadel tracks, as well as the level ''and'' hub themes for Empire City. The 360/PS3 version doesn't include the full length Gaia Gate theme, which only appears in a very short cut-scene in the HD consoles version.
* DamnYouMuscleMemory: If you've trained yourself to instinctively press the jump button in midair near an enemy, you may have to readjust yourself, since the homing attack was moved to share the same button as the boost in the PS3/Xbox 360 versions.
* DarkIsEvil: Although Sonic has the same personality in his fierce looking 'werehog' form, this is only because of his [[HeroicWillpower strong heart]]. All other characters influenced by Dark Gaia become either evil or depressed at night, although a few possessed citizens simply reverse their personalities, making laid-back, meek characters manic and cheerful instead.
* DateRapeAverted: A G-rated version of this trope. Werehog Sonic stops Professor Pickle's possessed assistant from harassing Amy.
* DeadpanSnarker: Orbot takes every opportunity to snark at Eggman when things go wrong, much to Eggman's annoyance.
* DemonicPossession: Some of the townsfolk become possessed by Dark Gaia at nighttime, either making them depressed, evil, or have some other personality unusual from their normal selves. You can perform 'exorcisms' on them by giving 'em a flash with your camera and then "expel Dark Gaia from their hearts" by defeating waves of Dark Gaia enemies who suddenly appear.
* TheDevTeamThinksOfEverything: Along with the Hedgehog Engine, designed to make the lighting look as great as possible, Sonic Team also went to a lot of effort to make the animations look smooth. This included minor animations that didn't matter to the game but were pretty cool to be there in the first place. For example, when Sonic walks up to a set of stairs, he will put one leg onto the step in front of him. His idle animations even work with it.
** The NPC characters in the hubs are also surprisingly well fleshed out, and have their own subplots an sidequests, some of which span over the entire globe (Hualin from Chun-Nan leaves her village to do something other than make meat buns for the rest of her life, Eric and his wife visit Chun-Nan after it gets restored, Samara from Shamar gets hopelessly lost looking for her home country, etc). If you care to, you can end up doing a whole lot of rather pointless things that amount to little in the overall plot, but still have self-contained meaning.
** In Eggmanland on the PS3 and Xbox 360 version, if you attempt doing the second Werehog segment (the balance beam pipes) as the Hedgehog, the path to the next area will be blocked by a laser grid with an extra life in front of it.
* DieChairDie: The Werehog is actually rewarded after missions based on how many orbs (Dark Gaia Force) he collects, much of which can be obtained from destroying random scenery.
* DiggingYourselfDeeper: When Orbot snarks about how Eggman's plan is currently failing:
-->'''Eggman:''' That was... err... all part of my plan! Part of the big picture! Where's the fun in having my plans succeed without any challenge?!
-->'''Orbot:''' '''''...'''''
* DoesNotLikeSpam: Chip really dislikes spicy food and he and Sonic, of course, hates eating anything from Eggmanland. Curiously, Sonic's very low EXP gainage from (presumably nutritious) fish and seafood strongly implies that he hates both.
* DoubleJump: Sonic the Werehog.
* DramaticThunder: Shown when you first actually meet Dark Gaia.
* DummiedOut: The Wii/Playstation 2 version lost Empire City (and by correlation, the Skyscraper Scamper levels), all but one of the missions for Mazuri (the Egg Beetle boss, leaving out the Savannah Citadel levels), and quite a bit of the other missions.
* EarthShatteringKaboom: Basically the result of Eggman's big laser in the opening - although unusually for this trope, all of the planet's continents are wholly intact, atmosphere and all, merely floating a mile or so higher above the planet's core than usual. In addition, while this trope usually entails killing everyone on the planet, here absolutely nobody is worse for the wear, still living peacefully on the surface; the only issue is some earthquakes here and there, and the gaps between the floating continents being difficult to surmount without air transport. Sonic's objective is to reverse this and set all the continents back down onto the planet's core.
* EasterEgg[=/=]FreezeFrameBonus[=/=]ConsoleCameo:
** In the opening, [[http://www.youtube.com/watch?v=mqHxGoFERZw just before Eggman pushes the button that fires his laser]] (stop at 3:29), if you look down you can see a SegaDreamcast to the lower-left. Who knew Eggman of all people was a classic gamer?
** And it pops up ''[[http://www.youtube.com/watch?v=AxmmwTSDubk&feature=related again]]'', when Eggman is ordering [[spoiler: Dark Gaia]] to kill Sonic. Eggman is such a hardcore Dreamcast fan, he's willing to take it with him to [[spoiler: the end of the world!]]
* EasyAmnesia: Chip.
* EldritchAbomination: Dark Gaia is far and away the most monstrous and horrifying creature in the series, along with having the power to back up its menacing appearance.
* EnemySummoner: Big Mothers and Fright Masters.
* EskimoLand: Holoska.
* EssenceDrop: Enemies and objects contain bits of blue light which are dropped when they're destroyed or killed. These fill up the Unleashed Meter.
* ExpositionFairy: Chip, wings included.
* ExtraEyes: Initially, Dark Gaia has three green eyes and two small glowing eyes. When it transforms after having green eyes destroyed, it opens up seven more. That makes twelve eyes in total.
* EyeScream: [[spoiler: This is how Perfect Dark Gaia was defeated: a [[SuperMode Super Sonic]] to the eye.]]
* FanRemake: As a GameMod for ''VideoGame/SonicGenerations'', which ports over the levels of the day stages only and addressing much of the complaints about the original (no {{Padding}}, no TrialAndErrorGameplay, better controls, etc.)
* FantasyCounterpartCulture: Every continent in the game is a blatant {{Expy}} of a real-world location. To list them all:
** Apotos = Mykonos (an island in Greece)
** Spagonia = Western Europe, mainly Italy
** [[DarkestAfrica Mazuri]] = Africa, mainly West Africa.
** [[EskimoLand Holoska]] = the Arctic
** [[{{Wutai}} Chun-Nan]] = China
** [[{{Qurac}} Shamar]] = the Middle East, mainly Baghdad
** [[BigApplesauce Empire City]] = New York City (derived from the state of New York's nickname, the Empire State)
** [[JungleJapes Adabat]] = Southeast Asia, mainly Thailand
** [[AmusementParkOfDoom Eggmanland]] = Disneyland ([[BlatantLies well, it sounds like it should be...]])
* FeetFirstIntroduction: This is how the Werehog is introduced to Chip as Sonic was holding him upside down whilst he was awakening from unconsciousness.
* FetchQuest: Bringing the various souvenirs to Pickle. Fortunately, these quests are optional.
* {{Fireballs}}: Fire masters fire these.
* FireIceLightning: Possibly unintentional, but the Werehog bosses-- Dark Gaia Phoenix (Fire), Dark Moray (Ice), and Dark Guardian (can summon Lightning). There's also the [[spoiler:Egg Dragoon]], which attacks with all three elements.
* FloatingPlatforms
* FlunkyBoss: Dark Guardian, Egg Dragoon and a few others.
* FoeTossingCharge: The boost does this to everything that isn't either razor-sharp or explosive. In fact, many running sections consist of using the boost to knock enemies into other enemies.
* FoodPorn: The designers seemed to have a bit of a fixation on making beautifully rendered, realistic food alongside the cartoony characters.
* FreeFallFight: Fight against Egg Dragoon.
* FundamentallyFunnyFruit: The Dureek food item. Which are obviously the Sonic world equivalent of the Durian fruit. The inventory even describes them as the "King of fruits" and in a reference to their inspiration's [[LoveItOrHateIt love it or hate it]] reputation in the real world, also suggests that you "try it and see". Chip can't make up his mind about how he feels about them after being fed one but Sonic seems to absolutely love them going by the extremely high EXP value he gains from ''just one''.
* FunnyBackgroundEvent: During some cutscenes, while Sonic is talking to someone, Chip is doing something in the background, like swimming in the air, and only contributes to conversations when food comes up.
* GadgeteerGenius: Miles "Tails" Prower.
* GiantRobotHandsSaveLives: The Gaia Colossus saves an unconscious Sonic in his giant hand. Justified in that Chip slowed Sonic's descent before catching him.
* GimmickLevel: All the non-story non-DLC acts are based around some kind of gimmick:
** Windmill Isle: Grind Rails
** Rooftop Run: Homing Attack precision
** Cool Edge: Boosting across water
** Dragon Road: Directional Launchers
** Arid Sands: QTE Pads
** Skyscraper Scamper: Narrow pathways
** Jungle Joyride: Air Boost
* GlowingEyesOfDoom: The eyes of Dark Gaia's incomplete form.
* TheGoomba: Rexes in the Nighttime stages.
* GottaCatchEmAll: You have to collect medals, save people from spiritual possession, and gain powerup items to advance in the stages in the PS3/Xbox 360 version. This is simplified in the Wii/Playstation 2 version, where you only need to beat the stages and required missions and talk to the right people.
* GrievousHarmWithABody: Can be used on any night level enemy that isn't a Dark Titan or Big Mother. The flavour text for the Rex enemies even suggests trying this.
* GuideDangIt: In the [=Wii/PS2=] version, unlocking the last Chun-nan day mission requires you to [[spoiler:collect 150 secret items.]] And what's even worse, [[spoiler:unlocking the last Adabat mission requires you to collect ''all'' of them!]]
* HailfirePeaks:
** Adabat combines PalmtreePanic, JungleJapes and TempleOfDoom.
** Eggmanland combines EternalEngine, CircusOfFear and LethalLavaLand.
* {{Hammerspace}}: Chip has one.
* HeKnowsAboutTimedHits
* HelpfulMook: The Dark Bat enemies, which are harmless and give the Werehog something to hang on to. There are other variations, which follow [[GoddamnedBats another trope entirely]]. Then there are also fan enemies which can be used to kill enemies or solve a few simple puzzles.
** Whenever a Thunder Ball shows up next to water, chances are the game's telling to toss it into water ForMassiveDamage.
* HeroicSacrifice: [[spoiler: Chip/Light Gaia.]]
* HeroicWillpower: The reason Sonic is able to stay in complete control of his Werehog form.
* HighSpeedBattle: All of the Hedgehog bosses, as well as the Interceptor's appearances.
* HumongousMecha:
** [[spoiler:The Gaia Colossus. It's formed from all of the world's Gaia Temples, which are already pretty big.]]
** A majority, if not all of Eggman's machines apply as well, mainly the [[spoiler: Egg Dragoon.]]
* ImmortalImmaturity: [[spoiler: Chip.]]
* InCaseOfBossFightBreakGlass: All of the Day Bosses. And the Egg Dragoon too.
* InescapableAmbush: Most of the Werehog battles.
* KillItWithFire: Fire Masters shoot fireballs that set Sonic aflame, and are covered in a fiery aura until [[ElementalRockPaperScissors doused]]. Sonic can do this to other enemies when he's holding an Egg Flame.
* LampshadeHanging
** Jari-Thure comments on Sonic's [[HalfDressedCartoonAnimal lack of clothing]] when the latter first goes through [[SlippySlideyIceWorld Holoska]]:
--> "You underestimate the dangers of this land. How come you have gloves on but nothing else? You some kind of weirdo?"
** The [[AndYourRewardIsEdible Hot Dog Vendor]] in [[{{Wutai}} Chun-nan]] offers similar commentary to Sonic's [[{{Hammerspace}} unusual ring storage capacity]] upon completing any of his Ring Trials:
--> "Where do you stuff all the rings you pick up?! Don't they slow you down?"
* LandOfDragons: Chun-nan and everything about it.
* LetsPlay:
** By the same group (LetsPlay/{{Pokecapn}}, Kung-Fu Jesus, LetsPlay/{{Medibot}}, and [=IlluminatusVespucci=]) who did the [[LetsPlay/SonicTheHedgehog2006 infamous LP]] of ''VideoGame/SonicTheHedgehog2006'', plus [=MyNameIsKaz=]. Notable [[FunnyMoments Crowning Moments Of Funny]] can be found in Medibot's (successful!) attempt to identify all 288 items the goons picked up during the playthrough, Kung-Fu Jesus successfully and accidentally predicting that someone was at his door, and Kaz's spot-on impersonation of Professor Pickle -- skipped text and all. Also, their reaction to the final QTE against [[spoiler: Perfect Dark Gaia, where they had to mash a button '''''60''''' times when the most they had to do before was 16.]]
** A different playthrough was also done by [[HellfireCommentaries NTom64 and FastestThingAlive]].
* LevelsTakeFlight: Tails transports Sonic on his biplane once more for the two Tornado Defense stages.
* LighterAndSofter: [[{{Irony}} Extra ironic]] considering Sonic's not-quite-SuperpoweredEvilSide and Dark Gaia being the single most terrifying EldritchAbomination in the series to date, but Sonic Team still managed it somehow; ''Unleashed'' marks the point in the series where the 3D games started not to have such dark and serious plots.
* LightningBruiser: Sonic becomes one here, instead of being the usual FragileSpeedster[=/=]GlassCannon, since he only loses rings proportional to his ring count upon being hit (or down to the previous level, in the Wii/PS2's case) and keeps his speed and enough strength to destroy robots.
* LoadsAndLoadsOfCharacters: Averted; many side characters such as Knuckles and Shadow are absent.
* LoadsAndLoadsOfLoading: It's usually bearable, but it gets particularly bad when you have to switch between Hedgehog and Werehog modes for [[NintendoHard Eggmanland]] on the PS3 and Xbox 360 version, as the game has to load up a new Sonic and respective assets ''midstage'' every time you switch.[[note]]Five times, to be exact.[[/note]]
* LoadingScreen: In the HD versions (when switching between day and night), the Xbox 360 version focuses more on Sonic's transformation, whereas the PS3 verion has a medallion switching between it's sun and the moon sides.
* LongSongShortScene: The [[http://www.youtube.com/watch?v=VfJ0_tcqnc4 Gaia Gate]] music in the [=360/PS3=] version, which only appears in one cutscene.
* LostSuperweapon: The Gaia Temples [[spoiler:are really pieces of the [[HumongousMecha Gaia Colossus.]]]]
* LovecraftLite: The game has shades of Lovecraft's works, especially the backstory behind Dark Gaia, but it has a little bit in common with classic mythological origin/apocalypse stories as well. Yes, there's a giant [[CombatTentacles betentacled]] monstrosity that destroys the world when it wakes up from an eons-long power nap, [[spoiler: but there's also a good entity that puts the world back together and sends Dark Gaia back into slumber.]]
* MacguffinEscortMission: Sonic's quest to deliver each of the seven depowered Chaos Emeralds to the seven Gaia Temples in order to repower them and restore the continents of the world.
* MacrossMissileMassacre[=/=]MoreDakka: Eggman pulls this off in the intro movie, trying to catch Sonic.
* MadeOfExplodium: One sled in Holoska's Cool Edge Act 1 Day stage explodes upon colliding with the side of an glacier. Sonic jumps out just in time.
** The rollercoaster car Sonic rides in Eggmanland, with spontaneously explodes without warning ''in midair''.
* MagicPants: Sonic's WhiteGloves rip off and his shoes change size and shape (and gain [[SpikesOfVillainy spikes]]) when he becomes the Werehog. They [[AddedAlliterativeAppeal reappear and revert, respectively]] when he turns back.
* MarathonBoss: [[spoiler: Dark Gaia]] is every bit as powerful as it has been built up to be and stubbornly refuses to stay down.
* MarathonLevel: Eggmanland, a six-act ([=Wii/PS2=]) or hour-long ([=360/PS3=]) gauntlet through [[EternalEngine Eggman's main base.]]
** ''All'' of the werehog levels are about three to four times as long as the day stages, and the day stages are already fairly long by speed level standards in the Sonic series (3-5 minutes). This is averted in the [=Wii/PS2=] version, though at the cost of a greater ''number'' of them.
* MetronomicManMashing: Sonic the Werehog can do this to some of the bigger mooks once he gets his elasticated hands on them.
* MultiPlatform: Besides the Wii, Playstation 2, Playstation 3 and Xbox 360 versions, a version for the ''mobile phone'', the gameplay of such will be more in tune to the ''Sonic Rush'' titles.
* MultiStageBattle: The Egg Dragoon fight, in which Eggman twice destroys the platform you're standing on.
* MusicalNod: [[http://www.youtube.com/watch?v=SiBWcaIA6hE Jungle Joyride (Day)]] contains a section from the ''SonicR'' song "[[http://www.youtube.com/watch?v=rTImh8gBfro Back In Time]]".
* NitroBoost: The Sonic Boost.
* NoNameGiven:
** Professor Pickle's assistant. Surprising, considering that ''every other NPC'' has a name.
** [[EveryoneCallsHimBarkeep Except for the Ice Cream Man.]]
** Orbot, who debuted in this game, didn't get his name until ''VideoGame/SonicColors''.
* NotSoHarmlessVillain: After supposedly getting overpowered with ease by Super Sonic, Eggman lures him into a trap and uses him as a power source to ''blow up the Earth'' after the hedgehog gets a bit too cocky with him.
* [[OneManArmy One Hedgehog Army]]
* OneHitPointWonder: Averted, he loses rings rings proprtional to his ring count when he gets hit in this game, with 20 rings being the minimum amount lost. The Wii/PS2 version drops you to the previous level instead (60, 30, or 0 rings, if you had 90+, 60-90, and 30-60 respectively).
* OurWerewolvesAreDifferent: Sonic the ''Werehog''.
* PainfulTransformation: Though it's not as explicit or as inhuman-looking as most examples, it's implied that Sonic's under a lot of pain when turning into the Werehog. It becomes really noticeable in ''Night of the Werehog'' (the in-house short released to promote the game), because for the last few minutes Sonic's been smiling and messing around - only to stop in front of a window looking out to the full moon, where he breaks into uncontrollable shaking, nearly collapses and (once it's all over) howls horribly.
* PalsWithJesus: [[spoiler:Sonic's pals with Chip, a.k.a. Light Gaia]].
* PauseScumming: Since the game doesn't hide the QTE prompts when you pause, if you pause every single time the moment a prompt shows up it gives you plenty of time to see it and hit the correct buttons. This is very helpful in the Tornado Defense stages.
* PersonalSpaceInvader: The Egg Shackles and the Egg Bursts sticks to Sonic and slowly takes rings away before (in the case of the Egg Burst) exploding.
* PhotoMontage: During Credits.
* PintsizedPowerhouse: The Dark Guardian, a boss, is this when compared the other bosses: It's tougher than a Big Mother or a Titan (Although way easier to beat than the latter). Can you believe it's barely any taller than a Deep Nightmare?
* PivotalBoss: Dark Moray, in either version.
* PopQuiz: In HD versions, some of the people in hub worlds can give you some of them.
* PressurePlate: In the Nighttime levels, they sometimes appear as a means to open up pathways.
* PressXToNotDie:
** Jungle Joyride Act 1 and Eggmanland are chockful of this sort of quick time events.
** [[spoiler:The HD version's final boss gives us [[PressXToNotDie Press X]] ''[[UpToEleven 60 times]]'' [[PressXToNotDie To Not Die.]] ]]
* {{Pun}}: The hot dogs sold in Holoska? "Chilly" dogs.
** One of Eggman's boss machines, Egg Devil Ray, is most probably called so because it attacks you with laser beams. However, the main unit happens to be shaped like an electric ray (as in, a fish). Good like realising this if you're not a native English speaker - or just happen to not know fish in general.
* PuzzleBoss: Shamar's boss, Dark Guardian (at least in the [=PS3/360=] version. The [=Wii/PS2=]'s version is a straight-up brawl.)
* QuadDamage: One of the powerups in nighttime stages boosts attack.
* RamenSlurp: Sonic is shown doing this in the photo montage in the credits.
* RecurringTraveller: Salesman Wentos.
* RespawningEnemies: [[HelpfulMook Helpful Mooks]] tend to respawn when killed or destroyed.
* ReverseCerebusSyndrome: After some pretty bleak games in the era following ''VideoGame/SonicAdventure2'', ''Unleashed'' sheds the darkness for a happier theme. The colors in the world and the art style are perkier and brighter than something like ''VideoGame/SonicTheHedgehog2006''.
* RewardingVandalism: Break pots and stuff, get items.
* RoarBeforeBeating: The Dark Moray roars before you actually battle it.
* RPGElements: The PS3/Xbox 360 version has them, where you can collect crystals to earn EXP, which you can then dump into various skills for both Hedgehog and Werehog to improve their abilities (with much more emphasis on the Werehog). The Wii/PS2 has a simplified version in the form of Dark Gaia Force, which automatically improves the Werehog's abilities at set intervals of Force collected.
* [[RubberMan Rubber Hog]]: Sonic's Werehog form has arms that can stretch.
* RunningOnAllFours: Sonic the Werehog does this to move faster as his legs are too short to allow easy running in bipedal stance.
* SatiatingSandwich: The Hero Sandwich food item, which provides a big 50 EXP when eaten by Sonic. They're amongst the best food items Sonic can eat in terms of EXP value.
* SceneryPorn:
** Particularly daytime stages in Playstation 3 and Xbox 360 versions, especially when you are in full motion. Nighttime ain't exactly ugly either.
** Hell, even the Wii/[=PS2=] version's quite a sight to see, particularly the Gaia Gates.
** The intro of the game (in both versions) shows a lot of it as well.
* ShesAManInJapan: Chip is a boy in the English version and [[NoBiologicalSex genderless]] in the Japanese version.
* ShipTease: Sonic and Amy.
* ShockwaveStomp: Titans like to do that.
* ShooOutTheClowns: During the final battle, [[spoiler:the comical villain Dr. Eggman, following his defeat in the Egg Dragoon battle, is swatted out of the center of the Earth by the monstrous Dark Gaia]].
* ShootTheMedicFirst: Well, they're called Heal Masters and all you've got is your fists but you've got the idea. Heaven help you if one shows up with [[BossInMookClothing Titan]] backup. Your death will be slow and painful.
* {{Shoryuken}}: Or more like Sho-Hog-ken and Sho-Claw-Ken.
* ShoutOut: One of Werehog Sonic's moves is called the [[StreetFighter Sho-hog-ken]].
** According to the [[UnlockableContent Directory]], Yasmine cannot decide on a team name and had chosen "[[Manga/FullmetalAlchemist Full Mettle Shamalchemists]]" two weeks ago.
** The final unlockable video (at least in the PS2/Wii version) is clearly based on a scene from [[spoiler: WesternAnimation/KungFuPanda.]]
** Also, the final battle in the Wii version appears to have a homage to [[spoiler:VideoGame/PunchOut]]
* SmallAnnoyingCreature: Chip in the Wii version. He is much less so in the PS360 version, since he only speaks up during gameplay if you walk into an assist icon, thus reducing the StopHelpingMe quotient. His cutscene antics are actually pretty funny most of the time.
* SmashMook: The Titans.
* SoundtrackDissonance: During the credits, "[[http://www.youtube.com/watch?v=AfiRbKgcKA0 Endless Possibilities]]" (Sonic's theme; 90's pop rock) plays first, while "[[http://www.youtube.com/watch?v=PJOQ8OPd7UE Dear My Friend]]" (Chip's theme; a slower, more somber song) plays second. The [=Wii/PS2=] version's credits show various scenes from the game, in chronological order-- thus, the first song plays while they show cutscenes from the beginning of the game, and the second song plays mainly during scenes from the last few levels. In short, the song about friendship plays while you see [[spoiler:[[{{Squick}} Dark Gaia turn into Perfect Dark Gaia]].]]
* TheSpiny: Enemies covered in electricity cause CollisionDamage. You can turn this on other enemies, too.
* StalactiteSpite: Some icicles in the daytime stages for Holoska tend to fall when approaching them.
* StealthInsult: Orbot manages to sneak a few in, though he's usually more upfront with his snark.
--> "Your skills at self-aggrandizement are unparalleled."
--> Eggman continues to laugh evilly for a few moments, before realizing what he said and smacking him.
* StylisticSuck: When you get an E rank, the [[http://www.youtube.com/watch?v=WX6BGd4iGm0 rendition of the main theme]] that plays is hilariously awful.
* SuperDrowningSkills: Averted in the daytime stages, as long as you're running fast enough (see WalkOnWater below). Nighttime stages aren't so lucky-- the Werehog ''sinks like a rock''.
** Sonic the Werehog doesn't actually sink when he touches water; rather, he inexplicably drowns instantly as soon as his head touches water, and his body floats to the surface.
* SuspiciousVideoGameGenerosity: Right before the final room in [[NintendoHard Eggmanland]], a group of canisters opposite the switch that opens the door conveniently provides all three power ups for you. [[SchmuckBait Guess what's in the next room?]]
* SymbolSwearing: Chip's reaction to eating the [[MasochistsMeal Canned Horror]].
* ThemeParkVersion: With the exception for Eggmanland, all the continents are thinly veiled analogues of real-world locations.
* ThemeSongPowerUp: [[http://www.youtube.com/watch?v=Td1XgkybCdo Endless Possibilities]] got a completely [[http://www.youtube.com/watch?v=2g6K-gsnGlE orchestrated remix]] for its [[FinalBoss Final Boss]].
* ThroatLight: Dark Gaia, who has purple light emanating from deep within its throat.
* TrademarkFavoriteFood: Sonic and his chili dogs, as well as Chip and his ubiquitous chocolate bars. Professor Pickle is also very particular about his cucumber sandwiches. [[PunnyName Which double as a clever reference to his name]], as pickles are made from cucumbers.
* TrialAndErrorGameplay: The last acts in the game, particularly [[MarathonLevel Eggmanland]], have no other way to win aside from dying tons of times and memorizing all the hazards by heart. The level designers were apparently aware of this, given that 1-up tokens (which mercifully respawn on death this time, unlike Sonic '06) are often located in front of checkpoints preceding some of the more frustrating sections.
* TrueFinalBoss: Averted; this is the first game in the series where the Super Sonic battle doesn't need to be unlocked with any extra effort.
* TurnsRed
* TwinkleInTheSky: This happens to Eggman in the [=PlayStation 3=]/Xbox 360 version of the fight with Egg Dragoon, after Sonic rips and flings him out of the mech.
* TwinkleSmile: In the [=PlayStation=] 3/ Xbox 360 version of the fight with Dark Gaia, Sonic does this right before destroying its third eye.
* UnexpectedGameplayChange: The Tornado Defense Acts in the [=PS3/360=] version.
* UnmovingPlaid: It's ''very'' subtle, but in the PS360 version, a static swirly vapor-like texture can be seen through [[EldritchAbomination Dark Gaia's creatures.]]
* UnusuallyUninterestingSight: All the anthropomorphic characters, but especially the Werehog. Most of the human characters don't seem to care much about a hairy monstrosity with spiky shoes and super stretchy arms.
* VariableMix: When Sonic uses his speed boost, the bass instruments of the background music almost disappear due to the air rushing by.
* VerbedTitle
* VideoGameCrueltyPotential: Enemies in Werehog stages don't actually [[EverythingFades fade]] until their death animation ends. Any attack interrupting that just resets the animation. Knowing that, one can spend as long as they wish keeping the poor abomination on the edge of life and death to rack up a combo.
** You can attack citizens to your heart's content, and they'll react accordiglngly.
* VideoGameSettings:
** CircusOfFear [=/=] EternalEngine [=/=] LethalLavaLand [=/=] '''MarathonLevel''': Eggmanland.
** GraffitiTown: Skyscraper Scamper, Rooftop Run, Arid Sands, Windmill Isle.
** GreenHillZone: Windmill Isle and Savannah Citadel.
** PalmtreePanic [=/=] JungleJapes [=/=] TempleOfDoom: Jungle Joyride.
** ShiftingSandLand: Arid Sands.
** SlippySlideyIceWorld: Cool Edge.
** {{Wutai}}: Dragon Road.
* VillainExitStageLeft: Eggman in the opening when Sonic goes Super...or at least it seems like he was, only to reveal he was just luring Sonic into his trap.
* VocalEvolution: Jason Griffith's Sonic is ''far'' more emotional and energetic than all of his prior roles as Sonic. Apparently, he took some voice training after ''Sonic 06''.
* VoiceGrunting: Both versions have this outside of cutscenes.
* WalkingDisasterArea: Pretty much everywhere Sonic runs, he leaves a lot of debris of destroyed public property.
* WalkOnWater: ''Run'', rather; this is required in several daytime stages. If you go any slower than top speed, [[SuperDrowningSkills Sonic will sink]]. This is taken to purely absurd levels in [[SlippySlideyIceWorld Cool Edge]] Act 2 and the DownloadableContent stage Dragon Road Act 5, which are ''composed almost entirely of water''!
* WalletOfHolding: {{Lampshade|Hanging}}d after completing some ring trials: "Whoa! Where do you stuff all those rings? Don't they slow you down?"
* WhosLaughingNow: ''Unleashed'' marks when Eggman finally ''succeeds'' in creating his dream amusement park of Eggmanland. [[NintendoHard It is every bit as unforgiving as you would expect.]]
* WhyWontYouDie: Said by Dr. Eggman halfway into the fight with the Egg Dragoon:
-->''"Stubborn little pincushion! Give up and die already!"''
* WorldTour: The game uses obvious {{Theme Park Version}}s, but they're not fooling anyone. Besides, in Japan it's even named ''Sonic World Adventure''!
* WreakingHavok: The Havok physics are much better implemented here than in the [[VideoGame/SonicTheHedgehog2006 last 3D adventure]]. It's best shown in sections where some enemies fly in front of you while you're at top speed to try to laser you, and the best way to beat them is to knock other enemies into them.