[[quoteright:341:http://static.tvtropes.org/pmwiki/pub/images/SonicAdventureCover_8990.jpg]]
[[caption-width-right:341: The fastest thing alive makes the comeback of a lifetime.]]

Created as ''[[KillerApp the]]'' [[KillerApp launch title]] for the SegaDreamcast, and the highest selling title for the system, ''Sonic Adventure'' is one of the first 3D games in the ''Franchise/SonicTheHedgehog'' series [[note]]Earlier entries such as ''Sonic3DBlast'' and ''SonicJam'' do not count, as the former [[DigitizedSprites was not real time 3-D]], and Jam's 3D world wasn't a full 3-D game, but a very early beta of Sonic Adventure, and while SonicR and SonicTheFighters used real time 3D, they were spinoff titles with different gameplay styles than the main series [[/note]]. It was released in Japan on December 23rd, 1998, receiving releases in Europe, North America and Australia between September and December of 1999.

''Sonic Adventure'' was designed to be to Sega and ''Franchise/SonicTheHedgehog'' as ''VideoGame/SuperMario64'' was to Nintendo and ''Franchise/SuperMarioBros'': a KillerApp designed to be the VideoGame3DLeap to an established mascot franchise that would not only showcase the potential of their flagship console, but also [[WinBackTheCrowd revitalize their flagship series and their own reputation]], after they had [[DorkAge fallen into both a creative and financial rut]] during their rocky SegaSaturn years.

Mad scientist [[BigBad Dr. Ivo "Eggman" Robotink]] has a new plan to TakeOverTheWorld: releasing an ancient morphogenic creature known as "Chaos" [[SealedEvilInACan from its confinement]] and using the seven [[MineralMacGuffin Chaos Emeralds]] to empower it to world-conquering levels.

Standing between him and his maniacal goals are a team of six heroes, whose adventures unfold in a RashomonStyle plot:

* [[ChronicHeroSyndrome Chronic Hero]] Sonic the Hedgehog, a sarcastic but virtuous blue hedgehog capable of running at supersonic speeds.
* Sonic's best friend, Miles "Tails" Prower: a young genius fox with an aptitude for building machines on par with Robotnik's creations.
* Knuckles the Echidna, the guardian of the Master Emerald within which Chaos was sealed. When the Master Emerald is shattered by Robotnik, Angel Island falls from its place in the sky and into the sea. Knuckles takes it upon himself to track down the missing pieces and restore the Emerald (and Angel Island) to its former glory.
* Amy Rose, a pink hedgehog with [[StalkerWithACrush an all-consuming crush on Sonic]]. After she meets a young bird on the run from one of Robotnik's robots, Amy resolves to return the bird to its family.
* Big the Cat, a lazy but warm-hearted fisherman who is seeking to rescue his best friend Froggy from the clutches of Chaos.
* E-102 Gamma, one of Robotnik's most advanced robots, who eventually turns against its creator.

''Sonic Adventure'' was generally praised as a revival for the series, which had been wallowing in spin-off games and remakes during the SegaSaturn era. However, a few points of criticism would haunt later iterations, like the gratuitous CameraScrew, GameplayRoulette, a few noticeable bugs, and slippery controls -- problems that have sealed Sonic's reputation as having having [[PolygonCeiling a subpar 3D leap]]. It has nevertheless remained popular among fans as a defining game for the sequels that followed.

A direct sequel, ''VideoGame/SonicAdventure2'', sold in 2001 to commemorate the series' [[MilestoneCelebration 10th anniversary]], and rumors of a third iteration of the ''Adventure'' series linger on, though some argue that ''VideoGame/SonicTheHedgehog2006'' was Sonic Adventure 3 in everything but name.

Re-released for the NintendoGameCube and PC in 2003 as ''Sonic Adventure DX: Director's Cut'' (ironically [[SequelFirst after its sequel's remake]]), which added special missions and unlockable GameGear games. As of September 15th, 2010, it is now available for purchase on XboxLiveArcade and {{PlayStation Network}}, with the ''DX: Director's Cut'' extras [[DownloadableContent sold separately]][[note]]but does not come with the GameGear games[[/note]]. Roughly half a year afterwards, it also saw a release in this manner on {{Steam}}.

[[foldercontrol]]

[[folder: Playable Characters and their gameplay types: ]]

# '''Sonic the Hedgehog''' -- Sonic's gameplay style is the most reminiscent of the side-scrolling games: Just get to the goal (which is sometimes an animal capsule reminiscent of the Genesis games, sometimes a Chaos Emerald, occasionally just an end area).
# '''Miles "Tails" Prower''' -- Sonic's lil' two-tailed fox buddy. All of Tails's stages pit you against Sonic (and later Robotnik) in a race to the end of the stage. The stages are just a single section of Sonic's stages, hopelessly broken by Tails' flying ability. [[TheComputerIsACheatingBastard Sonic is a cheating bastard]] for this very reason, but even speed boosts can't help him.
# '''Knuckles the Echidna''' -- Current Guardian of the Master Emerald. When Chaos is released from the Emerald, it is naturally broken into pieces. Thus, the goal of each of the echidna's stages is to find three shards, using his SpiderSense to pinpoint their locations. Reappeared in VideoGame/SonicAdventure2 for Knuckles and Rouge.
# '''Amy Rose''' -- In her stages, Amy must outrun Zero, a robot in pursuit of her, and get to the giant balloon that will carry her away. Zero is actually ''not'' after Amy, but instead the little bird she is carrying, who unbeknownst to her, has a Chaos Emerald in its locket. Amy is not very strong or agile, and carries a mallet for protection.
# '''Big the Cat''' -- After his pal Froggy swallows a strange looking jewel and runs away from home, Big chases after the frog. The goal of each of his stages is to fish Froggy out of a body of water; indeed, these sections qualify as {{minigame}}s, with little danger posed to Big himself. Nevertheless, Big's fishing pole can double as a weapon.
# '''E-102 "γ" (Gamma)''' -- Shoot things up and get to the end of the stage before time runs out, which can be increased by [[{{Combos}} combo-killing]] multiple enemies at once. Like Knuckles', this also was re-used for Tails and Eggman's modes in VideoGame/SonicAdventure2
# '''Super Sonic''' -- As in other games, the GoldenEnding requires powering Sonic into his SuperForm and taking out the TrueFinalBoss.

----
!!Sonic Adventure provides examples of the following tropes:

* AbridgedSeries: [[SonicAdventureAbridged Already has a page.]]
* AbsurdlySpaciousSewer: Averted with Station Square's sewers, played straight with those of Casinopolis (you get dumped in there if you lose a game of pinball and come away with less than 100 rings).
* {{Abusive Parent|s}}: Pachacamac.
* [[ADogNamedDog A Frog Named Froggy]]: Big isn't too creative with the names. Incidentally, he [[MeaningfulName is]] pretty large for a cat.
* AirborneAircraftCarrier: The Egg Carrier [[spoiler:and the Egg Carrier II]].
* AirVentPassageway: The game actually makes use of this trope a number of times in order to progress from level to level.
** For example, Sonic and Tails travel through the sewers of Casinopolis in order to find [[spoiler: the Chaos Emerald located there.]]
** This is also how Gamma and Amy choose to travel through the Hot Shelter in the Egg Carrier.
* AllIsWellThatEndsWell: At the end of the game, [[spoiler:as the characters are recuperating after their battle against Perfect Chaos, Tails invokes this trope verbatim, ignoring the fact that the city has been completely inundated and destroyed.]]
* AlmostOutOfOxygen: A staple of the franchise. That countdown music is unnerving.
* AlreadyDoneForYou: Given that the storylines (Apart from the Super Sonic storyline) are done in a RashomonStyle, expect this to happen very often.
* AnAesop: [[spoiler:WithGreatPowerComesGreatInsanity. The tragic story of the Echidna race and Chaos prove this.]]
* AndYourRewardIsClothes: [[spoiler:Getting all medals unlocks Metal Sonic, who is essentially a reskinned Sonic with slightly altered animations. You can only use him in Trial mode.]]
* AnimatedAdaptation: Was adapted into an arc in the AnimeOfTheGame ''Anime/SonicX''.
* AnotherSideAnotherStory: Play through the main story from 6 different perspectives. Each character also gets a piece of the backstory of Chaos and the echidna race, only by playing through all stories do you get the complete sequence.
** And the exact same scenes get alternate dialogue.
* ArtEvolution: [=SA1=] introduced the art style for Sonic and friends that would be used in future games. Amy was the one affected most by this, as she no longer looks like [[DistaffCounterpart a pink Sonic in drag]]. However, the Sonic-themed pinball table in Sonic's version of Casinopolis ''does'' feature stock artwork from the earlier games.
* AscendedExtra: Amy, originally a minor semi-recurrer beforehand, gained a prominent playable role in this and many titles following it.
* {{Badass}}: Sonic. Thanks to the new 3D presentation, we now get to see him outrun a killer whale, run down a building, and even [[spoiler:take out a water god.]]
* {{Balloonacy}}: A single balloon is all Amy needs to float away from Zero's grasp.
* BareYourMidriff: Tikal.
* BattleInTheRain: Sonic's first encounter with Chaos.
* BigBad: Eggman, of course.
** [[spoiler: Chaos eventually turns on Eggman and absorbs the Emeralds.]]
* BiggerOnTheInside: The Hot Shelter and Sky Deck suggests that the Egg Carrier is this.
* BlobMonster: Chaos, who's made of water.
* BookEnds: Knuckles's story begins and ends with him narrating how he was fated to stay forever on Angel Island guarding the Master Emerald. In the beginning, he mentions that he doesn't know why he was given this role in life, but in the end, he believes he is better off for that.
* BornAgainImmortality: The Chao can come back from death this way if raised correctly. In fact, dying and being reborn twice is one of the requirements for a Chao to become a perfectly immortal Chaos Chao.
* BossArenaIdiocy: The arena Amy fights Zero in is enclosed by an electric fence. If you knock Zero into the fence, it will reveal a button in its head. Hitting this button damages it.
** Knuckles would not have defeated Chaos 6 if it weren't for the ice robots scattered all over the arena (for Sonic's fight with Chaos 6, see TacticalSuicideBoss below).
* BossRush: Beating a story unlocks a minigame where you fight each of the bosses faced in that story one after the other (the exception being [[spoiler:Super Sonic]], whose story ''only'' consists of a single boss fight with some Adventure Field navigation beforehand).
** Also, Gamma only fights Beta [[spoiler:and Beta II.]] The other E-100s are left out.
*** Even Big only fights Chaos 6, but it's just for the sake of having the player fish out Froggy as fast as possible.
* BrokenBridge: Parts of the Mystic Ruins, including Angel Island itself, are blocked off by pedestals that require [[PlotCoupon magic stones]]. The same goes for Station Square, except that the keys are more mundane.
* ButNowIMustGo: [[spoiler:Both Tikal and Chaos.]]
* CallBack: Icecap first appeared as "Ice Cap Zone" in ''Sonic the Hedgehog 3'', and it opened with a snowboarding segment, too. Red Mountain's inner section is also clearly part of Lava Reef from Sonic & Knuckles. Both are set on Angel Island.
** Amy Rose has a {{flashback}} to her kidnapping in ''VideoGame/SonicTheHedgehogCD''.
%%* CameraScrew
* TheCameo: [[VideoGame/SonicTheHedgehogCD Metal Sonic]] and [[VideoGame/SonicTheHedgehog2 Mecha]] [[VideoGame/Sonic3AndKnuckles Sonic]] in the Final Egg.
** [[VideoGame/SonicR Tails Doll]] (along with puppet versions of Knuckles and Sonic) appear as training dummies in E-102's first level.
* CaptainObvious: Quite a few snarky moments in [=SA1=], if you look closely.
-->''(the Egg Carrier changes its shape)''
-->'''Tails:''' Oh look! It's changed shape! Did you see that?
-->''(Sonic gives him a weary look, and ignores him)''
-->'''Sonic:''' Darn! This makes it harder for us to get to the bridge
-->'''Tails''': I hate it when he doesn't listen.
** Also, in Gamma's story, although it's due to being a robot, it states:
--> '''Gamma'''(when transported into the past via a vision): "This presents a problem."
--> '''Gamma'''(after seeing what happened to Beta after defeating him at the beginning): "This is the wrong room."
* CasinoPark: Casinopolis.
* [[JustForPun Chaos]] [[ChaosArchitecture Architecture]]: Angel Island looks virtually nothing like it did in ''[[VideoGame/Sonic3AndKnuckles Sonic & Knuckles]]''. Here is [[http://fc09.deviantart.net/fs71/f/2010/045/b/c/Angel_Island_for_Sonic_FGX_by_Sonicman98.gif the original]], contrasted to [[http://images.wikia.com/sonic/images/8/8e/SA_Angel_Island_2.jpg the Adventure counterpart.]]
* CharacterDevelopment: Tails learns to take on troubles without Sonic's help, and he even musters the courage to stop Robotnik's attack on Station Square. Amy also goes from being a DamselInDistress depending on Sonic to save her to an ActionGirl beating up the very robot that constantly pursued her. Finally, E-102 Gamma learns about love and caring, which motivates it to stop being a mindless servant to Robotnik, go on its own mission, and make [[spoiler:[[HeroicSacrifice the ultimate sacrifice in the end to free the bird trapped inside]]]].
* ChekhovsGun: The Chaos Emerald inside the Tornado 2. It plays a major role in setting off the events for the Super Sonic chapter.
* ComicBookAdaptation: Was adapted in story arcs in [[ArchieComics Archie]]'s ''ComicBook/SonicTheHedgehog'' and also as what was notably the last new story arc in ''SonicTheComic''.
* TheComputerIsACheatingBastard: Present in Tails's stages, specifically of the RubberBandAI variety.
* ConsoleCameo: E-105ζ "Zeta" is made of six Dreamcasts [[http://info.sonicretro.org/File:E105.png located around the grey blocks under his cannons.]]
* ContinuityNod:
-->'''Sonic (to Knuckles):''' "[[VideoGame/Sonic3AndKnuckles Did Eggman trick you ]]''[[VideoGame/Sonic3AndKnuckles again]]''?"
** The music for Twinkle Park's hovercraft and Windy Valley's "The Air" segments are remixes of the Panic Puppet and Green Grove Zone themes from ''Sonic3DFlickiesIsland''.
*** And the second piece of music for Emerald Coast is a redo of Act 2 of Green Grove.
** One of Amy's flashbacks is of Sonic saving her in ''VideoGame/SonicTheHedgehogCD''. However, [[SuddenlyBlonde the models weren't changed]].
** When playing other characters' stories, your allies will sport any power-up accessories you picked up for them in their stories.
** After getting their powers drained by Perfect Chaos, the Chaos Emeralds look the same as the Super Emeralds looked like in Sonic3AndKnuckles in their power-less state (except for the size, of course), prior to being fully restored by the player.
* ConvectionSchmonvection: Sonic and Gamma can survive just fine in the incredibly hot volcano section of Red Mountain, with lava and geysers being the only hazards that damage them. Then again, this is true of all ''Sonic'' games where the characters don't suffer any ill effects from standing only a few inches above a lava pit.
* CrazyPrepared: Eggman. Not only does he have the God of Destruction at his command, he has a giant flying carrier (although it functions more like a battleship), [[spoiler:a second carrier to use against Chaos if it goes rogue, a HUGE missile stationed off the coast of Station Square should the Egg Carrier and Chaos be defeated]], and a giant base in the middle of Mystic Ruins.
* CriticalExistenceFailure: As in most games in the franchise, Sonic and the cast can take any amount of damage, from a barrage of Eggman's launched missiles to an explosion a third the size of the Egg Carrier, without any outward sign of injury, but after their last ring is lost, brushing against a robot chimp is enough for a K.O.
* CrystalPrison: The Master Emerald is this to Chaos.
* CurbStompBattle: In the final route of the game, [[spoiler:Robotnik hops into the Egg Carrier 2 to tame Perfect Chaos. It's onscreen for maybe 30 seconds before Perfect Chaos blows it up.]]
* CutsceneIncompetence: In some cutscenes, Sonic is just standing there.
* CutscenePowerToTheMax: Now we know why Sonic refuses to sit in the cockpit of Tails' plane -- because gravity means '''nothing''' to him. He survives falling several kilometers to the ground not once, but ''twice'' in the game. The second time, Sonic's body endures a comical pancake effect when he hits the ground, but he's no worse for wear.
* DarkerAndEdgier: At least in comparison to most ''Sonic'' games released before it. This game literally starts off with its opening cutscene depicting a city being flooded by Perfect Chaos, and later in the game, [[spoiler:the echidna tribe crosses a MoralEventHorizon]].
** Gamma's story is this to the rest of the game, complete with an explicitly BittersweetEnding. Super Sonic's story has a somewhat grimmer tone than the rest of the game as well.
* DeadlyRotaryFan: E-06 Spinner and E-16 Electro Spinner are fitted with these. Speed Highway also features a HelicopterBlender obstacle.
* [[DidYouJustPunchOutCthulhu Did You Just Punch Out The God of Destruction?]]
* TheDragon: Chaos to Robotnik. [[spoiler:[[DragonWithAnAgenda If just to get the Emeralds.]]]]
** CoDragons: E-102 Gamma to a lesser extent plays a similar role to Robotnik [[spoiler:prior to a HeelFaceTurn]] helping in preserve his alternative Dragon.
* DragonWithAnAgenda: Chaos only helps Eggman to get the Emeralds so that [[spoiler:Chaos can go OneWingedAngel and destroy the world]].
* DuelingPlayerCharacters: The game has Sonic & Knuckles fight again, as well as E-102 Gamma. However, playing through as Knuckles & Gamma allows the player to fight Sonic, and playing as Tails puts him in the fights instead of Sonic.
* EasterEgg: Cream the Rabbit [[EarlyBirdCameo makes a short appearance]] in the remake. [[http://www.youtube.com/watch?v=wexxG6IaNi4&feature=related See video here.]]
* EggshellClothing: One of the Chaos.
* EleventhHourSuperpower: Super Sonic, at the very end.
* EldritchAbomination: Chaos, a slime creature whose innards can be seen through it.
* EliteMook: The E-100 series robots. Oddly despite their more advanced intelligence and power than Eggman's usual badniks (apparently enough to rival Sonic individually abiding by Gamma's story) they are mostly given mundane tasks by the doctor such as searching for a frog in a beach.
* EternalEngine: Final Egg.
* ExpositionFairy: Tikal is always there to guide the player.
* FailedASpotCheck: While it's not acknowledged by the characters themselves, during the Super Sonic/Final Story Sonic is shocked to hear from Tails that Angel Island has fallen again, despite the fact that he is lying down in view of where it fell.
* {{Fanfare}}: While addressing his robots, Eggman plays his own [[http://www.youtube.com/watch?v=fg3ezY6aDV4 canned fanfare music]]. Pretty amusing.
* FiveManBand:
** TheHero: Sonic
** TheLancer: Knuckles
** TheSmartGuy: Tails
** TheBigGuy: Big the Cat
** TheChick: Amy Rose
** TheSixthRanger: E-102 Gamma
* FiveRoundsRapid: The cops unloading their clips at Chaos 0.
** OH NO! OUR WEAPONS ARE USELESS!
* FixedCamera: Made more adjustable in the ''DX'' version.
* FloatingContinent: Angel Island before the Master Emerald was shattered, and Windy Valley.
* {{Foreshadowing}}: The fact that Tikal had actually managed to send Gamma's mental mind to the past foreshadows him [[spoiler: becoming sentient]] in his chapter.
* FreeRotatingCamera: Not universal though.
* FreudianExcuse: [[spoiler:Pachacamac retroactively gets one through ''VideoGame/SonicChronicles''.]]
* {{Friendly Playful Dolphin}}s: Dolphins jump around you in Sonic's first stage, "Emerald Coast", if you're looking in right place at the right time. The appearance of these dolphins and their numbers seems to be performance based, or it might be random.
* {{Futureshadowing}}: Some of the visions of the past do this. No, seriously.
* GameBreakingBug: Windows will crash in certain times in ''DX''. Most notably the fight with Dr. Eggman in the Mystic Ruins.
* GameMod: Sonicretro has made one for both PC versions [[http://forums.sonicretro.org/index.php?showtopic=25301&st=0 that fixes much of the bugs and other oddities in the original release]].
* GameplayAndStoryIntegration: In the Chao Gardens, Chao have ResurrectiveImmortality as long as they're properly cared for. In the story, [[spoiler: the Chao who were Chaos' friends kept living through the generations until they were able to meet up with him again in the ending.]]
* GameplayRoulette: ''Sonic Adventure'' was where all of the {{Unexpected Gameplay Change}}s the ''Sonic'' series became infamous for started.
* GoingThroughTheMotions: Not a major example, but quite noticeable in Amy's ending when she performs her boss victory animation and then abruptly snaps back to her standing animation.
* GoThroughMe:
** In the {{backstory}}, Tikal tries to defend the Chao and the Chaos Emeralds from her dad and his soldiers. Said soldiers brusquely push her aside and proceed to incur Chaos' wrath.
** In the aftermath of Sonic's (or Tails') fight with Gamma, [[TheRashomon regardless of who wins]], Amy intervenes to convince the victor to let the other live.
* GratuitousEnglish: Sonic in the Japanese dub sometimes speaks English with a [[JapaneseRanguage thick accent]], such as when he tells players to "Serect yo kaakta!"
* GravityScrew: Most notably in Lost World, where panels on the wall glow when orientated correctly by hitting a switch, allowing Sonic and Knuckles to simply walk up the wall. The last part of Sky Deck changes orientation as well, and Knuckles can actually control this.
* HallOfMirrors: A segment exclusive to Amy's version of Twinkle Park.
* HeroicSacrifice: [[spoiler:Before the events of Sonic Adventure, in order to save the world from Chaos' destruction, Tikal sealed him, along with herself, in the Master Emerald.]]
* HijackedByGanon: Inverted by [[spoiler: Chaos taking over the role of central villain from Eggman in the final story.]]
* HintsAreForLosers: Touching one hintball in Knuckles' B-rank missions disqualifies you from getting the Emblem.
* HongKongDub: The lipsyncing is just plain bizarre and off a lot of the time.
* HubLevel: Station Square, Mystic Ruins, and the Egg Carrier.
* HundredPercentCompletion: Getting all of the emblems entails beating the action stages again, under more challenging circumstances. At most, you have to:
** Sonic: Finish each action stage within an allotted timeframe.
** Tails: Beat Sonic or Robotnik again (they're faster).
** Knuckles: Same as Sonic, only the allotted time is one to two minutes.
** Amy: Same as Sonic.
** Big: Catch a fish weighing in at 2000 grams and catch Froggy.
** E102 Gamma: Finish each stage within a certain amount of time left on the clock.
* ICannotSelfTerminate: Played with during Gamma's story. Gamma is perfectly capable of self-terminating, it's just that up until the penultimate boss Gamma dosen't realize that his self-given mission technically ''requires him to kill himself''. The moment of contemplation concerning his mortality that he has when he realizes this is almost heart-breaking despite almost no dialogue or music being present in the scene. He ends up averting this trope and allows himself to die from his injuries so that the Flickie inside of him can be freed.
* ICantBelieveImSayingThis: Knuckles says this, agreeing with Tails that Sonic is the only one who can harness the true power of the Chaos Emeralds after Perfect Chaos absorbed their negative energy.
* IOweYouMyLife: Not directly stated, but E-102 Gamma's resolve to rescue the animals trapped inside the E-Series robots was partly due to Amy saving its life.
** Said act by Amy was also provoked by Gamma freeing her and Birdie from Eggman's cell inside the Egg Carrier (which would later crash land into the ocean) making it both issued and returned at the same time.
* ISOStandardUrbanGroceries: The brown paper bag Amy carries in the introductory cutscene to her story.
* IWantSong: Tails's and Amy's themes: ''[[IJustWantToBeSpecial Believe in Myself]]'' and ''[[StalkerWithACrush My Sweet Passion]]''.
* IdiotBall: All three incidents when Sonic and Tails lose Chaos Emeralds to Robotnik. The third time this occurs, when two Chaos Emeralds are knocked out of Sonic/Tails's {{Hammerspace}} (depending on what character you're being) by a sharp impact. He then proceeds to '''lie there''' while Robotnik lazily floats over and [[TractorBeam beams them up]].
* IgnorantOfTheCall: Most of the cast react this way to Tikal's flashbacks. Near the end of his story Sonic fails to get the message that he should go after Chaos instead of Robotnik.
* ImplausibleDeniability: Knuckles seems to pull this off after Sonic asked him if he got tricked by Eggman again. This quote from Knuckles' story sums it up:
-->"Like, you weren't?"
* InCaseOfBossFightBreakGlass: The Egg Viper.
* IncomingHam: Robotnik has this moment after Sonic beats Chaos 0. "You know NOTHING, fool, It's ''CHAOS'', the '''GOD''' of '''DESTRUCTION!!!!'''"
* IndyEscape: At various points in Sonic's storyline, he has to evade the jaws of an angered orca, an avalanche and an ''Franchise/IndianaJones''-esque flaming boulder.
* InstantAwesomeJustAddDragons: There was going to be a dragon boss in the Sky Chase minigame, but it was removed...[[http://www.youtube.com/watch?v=AqLh2U7Mv2s But not entirely, however...]]
* InsurmountableWaistHighFence: Right towards the end of Twinkle Park for Sonic, there's an iron gate blocking you from getting to a spring if you end up on the right side of it. You can barely jump higher than it by yourself and you can definitely jump higher than it if you get up some speed with a Spin Dash. However, the game won't let you pass it from that side, you have to circumnavigate the entire circular roof to approach the spring from the other side.[[note]]However, unlike other examples, this CAN be circumvented by simply jumping at the spring from one of the floating platforms leading to the roof. If you execute a homing attack at it, the game won't block your progress, which is good for the A Emblem.[[/note]]
* KaizoTrap: Egg Viper. The camera angle isn't great either, so even if you know his suicide attack is coming, you won't be able to tell where he's gonna hit so you may still die anyway. Cue rage.
* KarmicDeath: Implied. Chaos absorbs the Emeralds to transform into Perfect Chaos, wiping out Pachacamac and the echidnas for all of their actions towards Tikal and the Chao.
* KickTheDog: Robotnik does it a ''lot'' in this game. He's portrayed as a lot more evil here than in most portrayals.
** In the flashback of the final story, Pachacamac ordered the echidna warriors to charge to the Emerald shrine, in which they trampled Tikal and injured the Chao, just so they can seize the Chaos Emeralds. Chaos didn't take kindly of this.
* KnightOfCerebus: Chaos. He is the first major threat Sonic and co. face that has ''no'' humorous quirks or traits whatsoever in persona and design; while his threat is genuine, he isn't seen as much more than a [[TheDragon Dragon]] to Eggman [[spoiler:until the climax and finale, when things truly take a turn for the worse when he finally turns on Eggman and gets all of the Emeralds.]]
* LargeHam: Eggman, Eggman, [[RuleOfThree Eggman.]]
-->"YOUUUUUUUUUUU KNOOWWWWWWWWWW NOTHING, FOOOOOOOOOOOOL! It's ''CHAOS! The GOD! OF DESTRUCTION!! [[EvilLaugh HAHAHAHAHAHAHAHAHAHA!]]''"
* LastNoteNightmare: "Fakery way" for Twinkle Park starts out in a quiet, cute tone, but slowly becomes much more creepy and menacing.
* {{Leitmotif}}: Every character is accompanied by their theme tune when they appear.
* LensFlare: Present in some of the cutscenes, as well as Emerald Coast.
* LethalLavaLand: Red Mountain, [[HailfirePeaks combined with]] some DeathMountain.
* LevelsTakeFlight: Sky Chase Zone reappears, and allows Tails to actually fire upon incoming enemies with his Tornado.
* LongSongShortScene: A few jingles and themes were unused in gameplay or for purposes different from how they are labelled (eg. "Calm After The Storm" is labelled as the theme for the crashed Egg Carrier Adventure Field in the Sound Test, but is used only in a short cutscene in Gamma's story). Many tunes were also truncated and can only be heard in full in the games' official soundtrack.
* MacguffinDeliveryService: Sonic and friends do a ''terrible'' job of keeping the Chaos Emeralds away from Eggman.
* MalevolentArchitecture: Speed Highway, a highway that uses loop-de-loops, corkscrews and ''has gaps missing'', all while being high in the air.
* MamaBear: Amy to Birdie. In one instance, she adamantly refuses to give Birdie to Gamma, which then led to his change of heart. In the other instance which stands out more, Amy was [[BerserkButton enraged when Zero knocks out Birdie out cold]] and was very keen on bashing him with her hammer.
* MinionWithAnFInEvil: E-102 Gamma ultimately.
* MyGodWhatHaveIDone: E-102 Gamma states this in his story recap following releasing Amy and Birdie and disobeying Eggman's orders.
* MythologyGag:
** [[WesternAnimation/AdventuresOfSonicTheHedgehog "Ooh, I hate that Sonic!"]]
** The invincibility music quotes [[VideoGame/SonicTheHedgehogCD "Toot Toot Sonic Warrior"]] at one point.
* NiceJobBreakingItHero: Knuckles being tricked into fighting Sonic led the two colliding with each other. As a result, Sonic fumbles the two remaining Chaos Emeralds (one of them being green which Knuckles ''thought was a piece of the Master Emerald''), only for Dr. Eggman to steal them and power up Chaos into his fourth form. As Sonic best puts it:
-->'''Sonic''': Smooth move, [[JustForPun knucklehead]]!
* NiceJobFixingItVillain: Sonic does not have a way to defeat Chaos 6, but luckily Robotnik keeps dropping ice-spewing egg robots onto the battlefield that Sonic can use to freeze Chaos and hit him.
* NobodyPoops: Surprisingly averted. One Action Stage (Hot Shelter) contains men's and women's restrooms, both of which can be entered, though not used.
* OffscreenMomentOfAwesome: Somehow Big managed to fly Tails' highly advanced Tornado plane back to his home with zero experience. Sadly we see about a second of him taking off from the Egg Carrier. No Sky Chase minigame for you, Big.
* OffscreenTeleportation: Zero in Amy's levels.
* OhNoNotAgain: Knuckles says this when he is sent in a flashback in the past for the third time. Also, Sonic says this in his story after encountering Chaos, who has transformed into his 6th form.
* OneWingedAngel: Chaos in ''Sonic Adventure'' becomes Perfect Chaos when he drains the negative energy out of the Chaos Emeralds.
* PalmtreePanic: Emerald Coast.
* PalsWithJesus: Tikal and Chaos, God of Destruction.
* PantyShot: Amy belts one out in most of the cutscenes she's in, most prominently when you choose her in the character select screen. This is made unsettling by the fact that she's [[{{Lolicon}} only 12]].
* PapaWolf: Chaos to Tikal and the Chao as the echidnas had learned the hard way.
* PathOfGreatestResistance: Ever since ''Sonic Adventure'' introduced the Homing Attack, nearly all ''Sonic'' games since then have had paths identifiable (and accessible) only by finding a trail of stationary midair enemies. This is most commonly used to begin an expert path or for a shortcut; very rarely is it actually required.
* PinballZone: Sonic's version of Casinopolis features Sonic and {{NiGHTS}}-[[ShoutOut themed]] pinball tables. Naturally, ''Sonic'' is the pinball.
* PolygonCeiling - The camera and controls are a point of criticism to the game, and these would continue into later games, creating a bad 3D reputation for the series.
* PoorCommunicationKills: Rather than talk to Sonic about why he's after the Master Emerald shards, Knuckles instead immediately starts a fight with Sonic and Tails without reasonably asking the two directly about it, which could have prevented the whole fight in the first place.
* ThePowerOfFriendship: The bond of Sonic with his TrueCompanions allows him to unlock the full potential of Super Sonic with the Chaos Emeralds, although Tails does say that Chaos only absorbed the negative energy of the Emeralds.
* RashomonStyle: Who won in the character vs. character fights? It depends who you ask. Most of the dialogue was re-recorded for each story even when it doesn't need to be.
** In Sonic and Tails's stories, the character played as is the one who fights most of the bosses and puts the keys in the Mystic Ruins.
* RidiculouslyCuteCritter: This game introduced Chao to the series.
* TheRuinsICaused: [[spoiler:The team looking down upon the flooded Station Square post-Chaos.]]
* RuleOfThree: Tails' and Knuckles' stories has three bosses, Knuckles gets a vision of the past on three seprate occasions (Upon clearing stages 2, 4, and 5 (Whereas the other five characters' storylines gets one)) on his storyline, and Amy's storyline has three levels (The fewest level count any character has in this game).
* {{Sampling}}: [[http://www.youtube.com/watch?v=K4FLexYgadg "Red Hot Skull"]], the theme that plays in the underground section in Red Mountain, samples its drumbeat from a Hip-Hop remix of "Ghetto Red Hot" by Super Cat (the [[http://www.youtube.com/watch?v=s98VjXtBSvo instrumental version]], to be exact).
* SceneryPorn: It may look a bit dated now, but it was considered highly impressive back then.
* SealedEvilInACan: Chaos [[spoiler: was originally sealed in the Master Emerald along with Tikal when he was about to destroy the world, but in modern times, Robotnik freed him by destroying the Master Emerald. Subverted however that, when it turns out Chaos isn't actually evil, just very angry and vengeful.]]
* SealedGoodInACan: [[spoiler: Tikal, technically.]]
* SelfServingMemory: While it's not mentioned in the game itself, the official strategy guide gives this as the reason for any differences between the character's stories.
* ShoutOut: [[NightsIntoDreams NiGHTS]] appears in the backgrounds, and the "flying" Chao is shaped like him.
** A section of Lost World has you [[Film/RaidersOfTheLostArk being chased by a boulder]].
** [[Franchise/StarTrek Resistance is futile]], [[spoiler:hand over the bird!]]
** Amy's intro cutscene has a bag marked "YU-2 Mart". YU-2 was what Yuji Naka was credited as in the Genesis Sonic games.
* ShowerScene: Possible in Casinopolis with Sonic if you have him stand under a showerhead, whereupon he'll start scrubbing himself. Knuckles can also trigger the water spray, but he has no custom animation for it.
* SlippySlideyIceWorld: Icecap, with an IcePalace section.
* SmokeOut: Eggman employs a variety of these tricks, including a flash grenade and sleeping gas.
* SpinAttack: Tails can swipe his tails as an attack, which is upgraded to infinite spinning with the Rhythm Badge. Amy can do the Spin Hammer Attack and swing her hammer while spinning, but she can't move while spinning.
* SpoilerOpening: The opening trailer contains the destruction of Station Square and Chaos's final transformation. Since this is the first ''Sonic'' game with an unlockable secret finale, it may have been intentional to prevent players from putting the game down after completing Sonic's story. Or just to get some extra milage out of the lengthy FMV sequence.
* StockVideoGamePuzzle: Quite a few different puzzles appear at varying points across the levels and characters, notably in Lost World.
* StuffBlowingUp: Sky Deck is full of cannons and explosions.
* SuddenlyVoiced: ''Everyone''. The early games didn't even have ''subtitled lines''.
** Except Sonic and Eggman. [[http://www.youtube.com/watch?v=z0Qr0kSXGEg They talked]] in ''[=SegaSonic The Hedgehog=]''. (Ray and Mighty did too, but only Mighty reappeared, and even then only in KnucklesChaotix.) A few months later, Sonic sometimes exclaimed in SonicCD (Usually upon getting a OneUp).
* TacticalSuicideBoss: There are LOTS of them in this game.
** If Eggman never dug into the ground with the Egg Hornet, Sonic would have never destroyed it.
** Chaos 2 already has two very effective attacks: one has him bounce all over the arena as a giant ball, and the other covers the entire floor, so why does he have to try to punch Knuckles?
** Had Chaos 4 never popped out of the water, Sonic, Tails, and Knuckles would have never defeated him.
** When Sonic fights Chaos 6, Eggman throws ice robots onto the arena. All Sonic needs to do is attack the robot and throw it at Chaos to make him vulnerable. Chaos would have won had Eggman not gotten involved.
** Eggman should know better than to stick his head out of the Egg Viper.
*** He also should know better than to make its wheels separate from its body and move flat-side up.
* TeamRocketWins: Playing E-102 Gamma's story at least, which allows you to fight and defeat Sonic in battle (though Amy stops him just short of finishing the job). So far Gamma is the only Eggman droid to individually defeat Sonic in the games storywise (albeit [[RashomonStyle branching]] storywise).
* TeethClenchedTeamwork: Knuckles' theme "Unknown from M.E." has a verse which he views teamwork, especially in regards to Sonic:
-->''I have no such things as weak spots'' \\
''Don't approve of him, but you got to rely on him'' \\
''This alliance has a purpose'' \\
''This partnership is temporary.''
* TempleOfDoom: Lost World.
* ThatsNoMoon: The excavation team at the Mystic Ruins is flummoxed by a "mountain" which suddenly appeared from nowhere. Unbeknownst to them (and the player, at first), it's actually Angel Island.
* TheVoiceless: Chaos never says a word, and Tikal is the one who relies his feelings to the audience.
* ThemeSongPowerUp: Played with in the final battle against Perfect Chaos. "Open Your Heart" (the game's main theme and Super Sonic's personal theme, more or less) plays during the first half of the battle. After you hit Chaos a number of times, it revives and the second half plays out under Perfect Chaos' own theme. It's subverted because Super Sonic doesn't defeat the creature for good while his own theme is playing, inverted because Perfect Chaos' own theme ("Perfect Chaos Revival!") is what plays during the second half (after it's rejuvenated) so Chaos is the one powering up to its own theme, and averted because it doesn't do a lick of good anyway (it's already losing by the time its music starts up; you just have to land the finishing blow (or two (give or take)).
* TranquilFury: In contrast to his usual LargeHam, Robotnik's encounter with Tails in the Egg Walker has him speak this way. Surprisingly, it's very unsettling.
* UncommonTime: The boss music for Chaos 6 alternates between a 7/8 and a 4/4 time signature.
** "[[http://www.youtube.com/watch?v=6WaLw12XZcY Fanfare for Dr. Eggman]]" is in 7/4.
* {{Understatement}}: Gamma's concise nature of speaking creates such gems as "This is the wrong room" after accidentally walking in on his older brother being seemingly cannibalized for parts and upgraded while still active, or "This presents a problem" after being seemingly ''teleported back in time''.
* UnderwaterRuins: Lost World, in parts.
* UnusuallyUninterestingSight: Tikal and the other Echidna residents seem completely nonchalant about the heroes' presence, or even a ''friggin' robot'' in the flashbacks to the past. About the only reaction they will make is if the player attacks them or jumps on them.
* UpdatedRerelease: The [=GameCube=] ''DX'' version, which added some more character cameos (namely Cream) and a catalog of Game Gear games. Further upgraded with the PSN and XBLA, with trophy/achievement support.
* UpgradeVsPrototypeFight: Gamma the robot is made to fight his "brother" Beta, who is the more advanced of the two. To Dr. Eggman's surprise, Gamma wins, so he is charged with carrying out the doctor's missions. [[spoiler:Later, Beta is rebuilt and battles Gamma again. Gamma just barely manages to win again, but unlike the previous battle [[PyrrhicVictory it results in his death]].]]
* UtopiaJustifiesTheMeans: [[spoiler:Pachacamac's reasoning for wanting the Chaos Emeralds taken from the shrine. It does nothing to cover up his power hungry nature and lack of regard for life at that point.]]
* VideoGame3DLeap: The true first one after the isometric ''VideoGame/Sonic3DFlickiesIsland''.
* VideoGameCaringPotential: Chao. If you are nice enough to a Chao, it will have a big smile on its face and clap whenever your character picks it up. Beware, however, that being ''too'' nice to a Chao might result in the little guy getting a spoiled personality, making it throw tantrums even when only a little hungry. Balance is the key, but regardless, if the Chao is happy enough, it will reincarnate into a baby at the end of its life.
* VideoGameCrueltyPotential: Likewise, you can hit the Chao, throw it, put it in water and watch it flail if it doesn't know how to swim, make it starve, and all other sorts of things. Such abuse will result in the Chao crying a fountain of tears, blowing a raspberry at you, or if it's aggressive enough, it'll charge at you and futilely throw punches. If the Chao is more sad/angry than happy, it ''won't'' reincarnate at the end of its life. You can kill your Chao outright this way.
** To a lesser extent, as you play a stage as Sonic with Tails following you, you will find yourself attacking Tails. A few instances in doing this is by jumping infront of him or use a spin dash.
* VideoGameSettings:
** AmusementPark: Twinkle Park.
** CasinoPark [=/=] PinballZone [=/=] AbsurdlySpaciousSewer: Casinopolis.
** DeathMountain [=/=] LethalLavaLand: Red Mountain.
** EternalEngine: Final Egg and Hot Shelter.
** FloatingContinent [=/=] RuinsForRuinsSake: Windy Valley
** GraffitiTown: Speed Highway
** PalmtreePanic: Emerald Coast
** RemilitarizedZone: Sky Deck
** SlippySlideyIceWorld: Ice Cap.
** TempleOfDoom [=/=] UnderwaterRuins: Lost World.
* WhatMeasureIsAMook: E-102 Gamma's story deconstructs this trope by virtue of being a playable {{mook}}. (Well, an EliteMook, but still).
* WoobieDestroyerOfWorlds: [[spoiler:Chaos. He only acts antagonistacally because he has been sealed away so long]].
* YouHaveFailedMe: Robotnik sorta does this to Gamma's E-Series brethren after they fail to retrieve the Chaos-enhanced Froggy, dispatching E-105ζ Zeta for a torturous upgrade and demoting E-103δ Delta and E-104ε Epsilon to generic "badniks" in random areas.

----