[[quoteright:256:http://static.tvtropes.org/pmwiki/pub/images/sonic_the_hedgehog_cd_title_screen_fixed_1571.png]]

->''"To live a life of power, you must have faith that what you believe is right, even if others tell you you're wrong. The first thing you must do to live a life of power is to find courage. You must be ready to reach beyond the boundaries of Time itself. And to do that, all you need is the will to take that first step...''

->''Ask not what others can do for you, but what you can do for others."''

-->--Words taken from Japanese Cover of Sonic CD.

Released in 1993, ''Sonic CD'' was one of the better games that could be found on the [[SegaGenesis Sega CD]] (indeed some consider it among the greatest video games of all time), an ambitious SegaGenesis add-on marred by its price tag and an over-saturation of "FMV games." Considered by many to be one of the best ''Franchise/SonicTheHedgehog'' [[PlatformGame platformers]] thanks to the time travel elements and complex level designs providing much replay value. This game introduced Amy Rose Sonic's cute {{stalker with a crush}} and fan favorite [[EvilKnockoff Metal]] [[TheDragon Sonic]]. It also had an {{anime}} opening and ending sequences with Sonic displaying his {{badass}}ery; two of the few [=FMVs=] on the console that actually look good.

The story begins with Amy meeting Sonic, having used tarot cards to seek him out. When Amy inquires where he's going, Sonic says he's going to Never Lake, explaining that it's that time of the year when the Little Planet appears over the lake. Thanks in part to the seven Time Stones, the Little Planet does not abide by the passage of time familiar to inhabitants of their world, making {{time travel}} possible should one reach high enough speeds on the planet's surface. Being the lightning-quick, risk taking daredevil he is, Sonic is looking forward to visiting the Little Planet to see if he's fast enough to break the world's time barriers.

After arriving at Never Lake, the two hedgehogs notice something amiss. The Little Planet is there, but it has been chained to a mountain and its surface covered in metal. Arriving on the planet's surface, Sonic and Amy investigate, but soon Amy is captured by a figure that quickly flies away. In his search for Amy, Sonic encounters Dr. Ivo "Eggman" Robotnik, the {{mad scientist}} he had defeated before.

Robotnik and his loyal Badniks are in the process of transforming the entire Little Planet into his own dystopian fortress, and once he collects the Time Stones, [[TakeOverTheWorld taking over the world will be a breeze]]. That is, after killing Sonic first. When Robotnik discovered that Sonic had arrived on the Little Planet, he sent Metal Sonic, a robot painstakingly modeled after its namesake, to kidnap Amy and lure Sonic. With Sonic taking the bait, Robotnik hopes to destroy his arch-enemy. Determined as usual, Sonic must collect the Time Stones, defeat Metal Sonic, rescue Amy, and liberate the Little Planet from Robotnik's tyranny.

[[TimeTravel Time travel]] is the main gimmick of the game. The first two Zones in each level have "Past" and "Future" signs, and after hitting one of the signs and gaining enough speed, you'll either travel to the past or to the future. By default, the future is always a [[BadFuture bad one]], a desolate wasteland with worn down technology that ruined the environment. By destroying the Badnik generator in the past, [[SetRightWhatOnceWentWrong the Zone's future automatically becomes a good one]], with all advances in technology actually working to the environment's benefit, and the badniks in all three periods are automatically destroyed. The boss fight in each level is in zone three and takes place in the future, and if you've destroyed the generators in the previous two zones, the future is an automatic good one. However, if you go to the Special Stages and collect all seven Time Stones, all of the levels will automatically have good futures.

In addition to the Spin Dash, Sonic can do the Super Peel-Out, a technique that sends him dashing off with super speed. The difference between the two is that the Super Peel-Out gives Sonic a greater burst of speed but leaves him vulnerable to enemy fire and collisions. The Spin Dash operates very differently than in subsequent games, probably because it was in its preliminary stages before ''VideoGame/SonicTheHedgehog2''. It has to be "revved up" for several seconds before use.

Because of the above, and the fact that it was the first post-''Sonic 1'' game to enter development, ''Sonic CD'' is often considered to be [[{{interquel}} an in-between game]], following the events of the [[VideoGame/SonicTheHedgehog first game]] but taking place before the second; this is also backed up by the absence of Tails, who shows up in a secret picture with the caption "See you next game!", referring to ''Sonic the Hedgehog2''.[[note]]WordOfGod has recently stated that while it's canon, the game has no particular spot on the timeline, but has noted that ''CD'' will be closely tied to (and be the precursor for) ''[[VideoGame/SonicTheHedgehog4 Sonic the Hedgehog 4: Episode II]]'', but that won't affect ''Sonic CD'''s spot in the timeline.[[/note]]

The game was ported to the [[IBMPersonalComputer PC]] in 1996, and was later included in the ''[[CompilationRerelease Sonic Gems Collection]]'' in 2005, for the {{PlayStation 2}} and {{Nintendo GameCube}}.

''Sonic CD'' was [[VideoGameRemake remade]][[note]]completely from scratch using a fan-made engine[[/note]] in 2011, for the {{Xbox 360}} (through XboxLiveArcade), {{PlayStation 3}} (through the [[PlayStationNetwork PlayStation Network]]), PC (through digital distribution, primarily {{Steam}}), [[IOSGames iPhone, iPod Touch, iPad]], Android, and Windows Phone[[note]]announced with the others but not released until November 2012 alongside Windows Phone 8[[/note]] in HD with proper widescreen support. It marks the first time the Japanese soundtrack is officially available in the United States[[note]]besides its inclusion with a screensaver on ''Sonic and Knuckles Collection'' for the PC[[/note]], and the only version since the Sega CD (or Mega CD as it is called there and in Japan) that Europeans get it in (since the European PC and ''Gems Collection'' versions had the American soundtrack). [[AndAnotherThing It was also developed by]] [[PromotedFanboy Christian "The Taxman" Whitehead]]. [[http://www.youtube.com/watch?v=EJa-4tMqVNc&feature=player_embedded It was actually in the works for a while.]]

The remake features [[http://www.sonicretro.org/2011/11/sonic-cd-a-time-paradox-of-a-two-tailed-fox/ Tails as a playable character.]] Also featured is an option to select [[http://www.sonicstadium.org/2011/11/us-soundtrack-option-confirmed-for-sonic-cd-port/ either the Japanese or US soundtrack]].
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!!''Sonic CD'' is the TropeNamer for:
* BadFuture (also {{invert|edTrope}}s this trope when/if Sonic saves the future)
* PalmtreePanic

!! This game provides examples of:
* ActionBomb: Bigbom, a large version of Bomb from the [[VideoGame/SonicTheHedgehog1 first game]].
* ActionHoggingOpening: Also included in the package is an ending sequence that's equally just as action-packed.
* AddedAlliterativeAppeal: The level names. Ditto for the final boss music, "Final Fever."[[note]]Both soundtracks' final boss themes use this name, but unfortunately only the Japanese one is truly unique from the standard boss music, simply called "Boss!!" in both soundtracks, as time constraints ended up with the American soundtrack having a remix of the standard boss music.[[/note]]
* AdvancingWallOfDoom: During the Metal Sonic boss race in Stardust Speedway Zone 3, Robotnik will chase after Sonic shooting a laser from the bottom of his pod. If he hits Sonic, or if Sonic loses the race, it's an instant kill. The pod itself is also invincible.
* AirplaneArms: Sonic's max running speed has him do this, as well as his legs going into a infinity-symbol shape.
* [[AmericanKirbyIsHardcore American Sonic Is Hardcore]]: Elements from the Japanese soundtrack that were LighterAndSofter by comparison were replaced with something much creepier for the North American soundtrack. Nowhere is this more prevalent than the boss and Game Over music, which are both worthy of horror games; in contrast, the Japanese boss music was upbeat and seemed to take Sonic's side in the battle by saying Dr. Eggman doesn't stand a chance and sampling the "Work That Sucker to Death" lyrics from the Xavier song of that name, while the game over music just had a sample of the opening theme, "Sonic - You Can Do Anything" (specifically, the "toot toot sonic warrior" lyrics) that sounded like it was coming from a dying record player, as to indicate Sonic's adventure is temporarily coming to a halt.
* AlternativeForeignThemeSong: The North American version not only changes its theme song, but also changes four-fifths of the soundtrack[[note]]the "Past" music for each zone is exactly the same in both the American and Japanese versions probably due to technical issues, see "Painting the Medium" below[[/note]].
* ArcWelding: Because of this game's Wibbly-Wobbliness and never having had a place in the timeline, as of the remake it is now [[WordOfGod officially considered]] a predecessor to ''VideoGame/SonicTheHedgehog4''. As mentioned above, it's generally considered by fans to have taken place in between ''Sonic 1'' and ''Sonic 2''.
* ArtifactTitle: The 2011 remake is not distributed on a physical medium, let alone a CD.
* BackgroundMusicOverride: The race with Metal Sonic uses the ''Stardust Speedway - Bad Future'' theme even if you've achieved a Good Future in the level.
* BadFuture: TropeNamer. The Good Future that Sonic's goal is to make [[InvertedTrope inverts]] this.
* BonusStageCollectables: Time Stones.
* BottomlessPits: Almost entirely absent in this game, ''unlike'' just about every other ''Sonic'' game ever. Some exceptions...
** One of the obstacles in Metallic Madness Act 3 is a large bottomless pit with some [[PlatformHell tricky platforming]] above it.
** There's also one in the Present stage of Stardust Speedway Zone 1 right before the end of the level, but it's almost impossible to get down there and even if you do there is still a way back up. You have to deliberately kill yourself to fall into that pit.
*** There's also one in the Past of Stardust Speedway 2. Like the example mentioned above, there is a short wall and spring blocking the drop, meaning you have to ''try'' to fall down there.
** Changing time periods in an unexpected place in Palmtree Panic will sometimes cause you to de-warp in the middle of scenery. Usually, a little movement and jumping will cause you to glitch through the walls back into the stage proper (the programmers clearly expected this to happen), but on rare occasions it will drop you below the stage, killing you.
* BreakingTheFourthWall: As usual, Sonic gets impatient if he's [[IdleAnimation idle]]. Wait three minutes without pausing, and then he'll say, [[ScrewThisImOuttaHere "I'm outta here!"]] and proceed to jump off the screen, netting you a GameOver regardless of how many lives you have left. He shoots you an angry glare the entire time.
** In the 2011 remake, Tails yawns at you as usual. However, he won't force the game to end after three minutes of idling.
* BreakThemByTalking: The Bad Future theme of Metallic Madness in the Japanese soundtrack attempts to do this to [[TheFourthWallWillNotProtectYou the player]] by featuring a robotic voice saying some demotivational words: "You can't do anything, so don't even try. Get some help. Don't do what Sonic does. ...Sonic, dead or alive, is m-m-m-mine!" This is an inversion of a line from the theme song "You Can Do Anything": "...'cause if you try, you can do anything!"
* TheCameo: Tails shows up in the D.A. Garden menu and in a secret artwork advertising ''Sonic Drift''. For the 2011 remake, he is PromotedToPlayable.
* ComicBookAdaptation: In issues 26-28 of ''SonicTheComic'' and issue 25 of [[Comicbook/SonicTheHedgehog the Archie comic]].
* CosmeticAward: Destroying the Metal Sonic Hologram Projectors in the Past has no effect on the Futures or the ending, but it does make some animals appear.
* CreatorCameo: Composer Naofumi Hataya has a small cameo in the Japanese soundtrack -- he's the guy screaming in the background of Quartz Quadrant's BadFuture music. (The soundtrack on iTunes mentions this.)
* CutSong: The planned final boss music of the American soundtrack never made it into any version of the game because of a lack of time to get it in. Instead, a very slightly modified version of the regular boss music plays.
* CyberpunkIsTechno: The Japanese soundtrack gives the present time period of the technologically advanced Wacky Workbench a fast-paced and chaotic techno tune.
* DarkerAndEdgier: In comparison to the Genesis titles, due to the presence of the {{Bad Future}}s.
* DevelopersRoom: One of the cheat codes brings up a screen featuring the developers' time attack records.
* DevelopmentGag: During the Special Stages from early betas where they are unfinished, a [[GratuitousEnglish Engrishy]] message appears on the screen, telling the programmers to wake up and finish their jobs.
--> The programmer has a nap!
--> Hold out! Programmer!
* DistressedDamsel: Amy.
* DownerEnding: In TheStinger of the Bad Ending, [[spoiler:there's a time rift, and Little Planet reappears, covered in its metal casing and chained once more, implying Robotnik used the Time Stones to hit the ResetButton on his failure.]]
* DummiedOut: "Round 2", which was, apparently, a Desert/Ruins stage; a Special Stage, which can be accessed with a code; and some items. The desert level, now named "Desert Dazzle", was supposed to appear in the remake, [[FailureIsTheOnlyOption but all that remains of it is a secret teaser picture]]. The rumored Final Fever level/{{True Final Boss}} was scrapped again as well.
* EasterEgg: A statue in Wacky Workbench 1 [[note]]an angel statue in the past that gives rings, or a Robotnik statue that drops bombs in the bad future; finding the angel statue unlocks an achievement in the 2011 re-release[[/note]], some artwork, and a DummiedOut Special Stage.
** The Secret Sound Test in the original release contains a number of these. Entering the right combination of three (two in the ''Gems'' version) numbers will take you to several pieces of artwork, start a secret Special Stage, or unlock debug mode.
* EternalEngine: Metallic Madness and, to a degree, Wacky Workbench, as well as most of the Bad Future levels being combined with the current level trope.
* EtherealChoir: The Japanese final boss music has a woman singing in the background; there are no lyrics, so it's essentially a OneWomanWail with instruments.
* EvilKnockoff: Metal Sonic.
* {{Expy}}:
** According to [[WordOfGod Naoto Ohshima]], most levels, with the exceptions of Quartz Quadrant and Wacky Workbench, were made as more surreal versions of ''[[VideoGame/SonicTheHedgehog Sonic 1]]'' levels. Even the level theme order is the same. Sometimes the similarities are subtle, sometimes not:
*** In Palmtree Panic, the badnik Kamemusi looks like a Motobug and behaves like a Crabmeat.
*** Collision Chaos has a [[JustForPun Spring Yard]] at the end of both Zones 1 and 2. The second zone also has two goals, just like Spring Yard Act 2.
*** Tidal Tempest's graphics resemble Labyrinth's. The water current gimmick, which sends Sonic spinning underwater is used in the second zone.
*** Stardust Speedway shares its level theme and position with Star Light. It plays rather differently, though, besides being fast-paced.
*** Metallic Madness' spinning, disappearing and moving platforms and doors are all from Scrap Brain. There's also a GiantMook version of the Bomb badnik called Bigbom and each Zone has a unique background, just like Scrap Brain.
*** Kama-Kama, a badnik in Collision Chaos based on the Slicer from [[VideoGame/SonicTheHedgehog2 Sonic 2]], but with linear instead of homing projectiles.
** The Time Stones clearly fill in for the Chaos Emeralds.
* In addition Quartz Quadrant and Wacky Workbench strongly resemble Hidden Palace Zone and Cyber City Zone respectively, levels designed in the early stages of Sonic 2's development that didn't make it into the final games (although elements from them did). It's quite possible that this was a conscious move, as Sonic 2's developers had to cut several levels due to a tight deadline.
* FlowerMotifs: The badniks contain seeds which sprout into flowers, as opposed to the "animal battery" motif the series normally uses.
* GameBreakingBug:
** Move Sonic to behind the starting point (i.e. left of "0000") while using Debug Mode, and the game will crash. There is also a bug which stops the music from looping and the next level from loading should the player take too long.
** Also, there's a point in the Past of Metallic Madness where you have to navigate some springs. The problem is that in the original Sega CD and emulator versions of the game, you cannot reach the top platform. The only way around it is to try to get back to the present. If you can't, you are stuck. Extra platforms were added in the 2011 release to remedy this issue.
* GottaKillThemAll: You can get the good ending without beating any special stages by going to the Past in every zone and destroying a unique machine, which also destroys all robots in the past. Doing so also lets you go to the Good Future in the same level.
* GreenAesop: Yup, it's there. Pretty standard for early ''Sonic'' games.
** In the Bad Futures, it's notable that, because of Robotnik taking over, the environment is more or less in a state of disrepair (including the robots themselves, amusingly); but in Good Futures, it's shown that nature ''and'' technology can indeed be in the same place without disastrous results. For example, the Good Future of Palmtree Panic is inhabited by small monkeys and has a system of pipes that regulate the clear water in the area instead of spreading polluted water as in the Bad Future with the water being pumped directly to the palm trees, which now have star-shaped decorations in the middle of the leaves. This is in stark contrast to most Green Aesops, which usually believe and preach that harmony between nature and machine cannot exist.
*** Further examples: the Good Future of Tidal Tempest looks like some sort of giant hydroponic greenhouse with nutrient-rich green water; in the Bad Future, the plants are dead or roboticized, and the water is magenta.
* GuideDangIt:
** For players trying to destroy all the Roboticizing machines in the past, Wacky Workbench Zone 1's device is infamously difficult to reach on the first try. In order to reach the machine, you have to jump on top of a [[SmashingHallwayTrapsOfDoom crushing piston]] near the level's end, which sends you down the pipe where the machine is located instead of killing you as with most crushing pistons in the series, such as Metropolis Zone's in ''VideoGame/SonicTheHedgehog2'' and, incidentally, Metallic Madness in this game, which has them work as in most of the rest of the series. (Fortunately, it's possible, albeit difficult without the skill and/or SaveScumming, to have all the Time Stones by this point for those who don't want to bother with the machine)
* InconvenientlyPlacedConveyorBelt: Everywhere in Quartz Quadrant. In the past they move fairly slowly, in the present they are average speed, and in either of the future stages, they move pretty damn fast, so getting past them can be a bit annoying. You can change the direction they go in, but it doesn't always help.
* ImpactSilhouette: Can happen in Palmtree Panic 1 Present and Past if Sonic enters a tunnel in the middle of the level.
* ImprobableAimingSkills: During the bad ending, [[spoiler:just look at the trajectory that Sonic's rock makes as he throws it at Robotnik.]]
* IndecipherableLyrics
** The Japanese Metallic Madness Present theme has a verse which is pretty much unintelligible. The only parts that are understandable are "Get yourself ready for a fight" and what sounds like "Yo, [[ScrewThisImOuttaHere we're outta here!]]"
** Also from the Japanese soundtrack, the boss music can be hard to understand aside from the "Work That Sucker to Death! Come on now! Work That Sucker to Death!" chorus and the spoken part that describes the foregone conclusion of the boss himself not standing a chance.
* InsistentTerminology:
** Whoever's behind the terminology in the series decided that what most ''Sonic'' games call an act, this game would call a zone.
** What are usually zones in ''Sonic'' games are called "rounds" here. "Act" is nowhere to be found anywhere.
* {{Leitmotif}}: The Japanese boss music for Robotnik, due to part of the lyrics:
-->The war began. Earth trembled in fear. [[BaldOfEvil Bald]], [[EvilGenius brainy]], and [[BigBad cold-hearted]]. The distance grows closer, little by little. Wow! [[MadScientist The power he possesses is incredible]]! [[ForegoneConclusion He doesn't stand a chance]]!
* LoopholeAbuse: Despite having a ten-minute limit per act, it's possible to spend far more time than that in any one level. [[spoiler:A successful time warp will revert the stage timer back down to five minutes. If you've been playing for less than five minutes, the timer will be unaffected. Also, if you're in debug mode, the timer doesn't seem to work at all. Just '''''don't''''' go too far to the left.]]
* MacroZone: Some of the end of Metallic Madness Zone 2 where Sonic goes tiny. He still retains normal jump height though.
* MissingSecret: For those who aim for 100% completion, Metallic Madness can be puzzling at first when it comes to finding Metal Sonic projectors. In fact, it doesn't have any.
* {{Mondegreen}}: The music with lyrics (which is several tracks except for past music) may end up getting misinterpreted since it was made for older hardware. For example, look up the Japanese boss music on [=YouTube=] and see how many people hear the lyric "Work that sucker to death" incorrectly, with mishearings such as "Work that toaster to death" and "Work that son of a [[PrecisionFStrike bitch]]."
* MookPromotion: The Hotaru badnik from Stardust Speedway later shows up as the mid-boss before the final boss.
* NoFairCheating: Debug mode can be unlocked in the remake, but while it's on you can't earn achievements and zone times won't be recorded.
* NoNameGiven: With the exception of Metal Sonic and Palmtree Panic's boss, EGG-HVC-001, the bosses lack names.
* NoOSHACompliance:
** Wacky Workbench, a factory where the ground floor bounces things high up into the air at random intervals (or constantly in the Futures).
** Quartz Quadrant wouldn't fit OSHA standards either with spikes everywhere.
* NonstandardGameOver: Put the controller down. Three minutes and one "I'm outta here!" later...
* OurFounder: The statues of Robotnik at [[EasterEgg Wacky Workbench]] and Stardust Speedway (Present and Bad Future), and the image on the mountain that appears in the opening (unfortunately, the close-up of the mountain tends to be cut in the rereleases).
* OxygenatedUnderwaterBubbles: Present throughout Tidal Tempest. Robotnik uses them as a shield in that level's boss that you can breathe through and attack him for a OneHitKO.
* PaintingTheMedium: The Present and Future music tracks are in Red Book audio (i.e. standard Compact Disc Digital Audio, or CDDA), while the Past songs are in the ''lower quality'' PCM format used by the Sega CD's PCM chip.
* PinballZone: Collision Chaos.
* PressXToDie: In the Sega CD version, pressing one of the jump buttons while the game is paused will restart the level at the cost of one life [[spoiler: provided you have at least two lives available. Otherwise, this reverts the player back to the title screen.]]
* PromotedToPlayable: Tails is unlocked in the 2011 remake just by beating the game once as Sonic, with no other criteria. He actually makes the game ''easier'' due to his ability to fly and swim taken from ''{{VideoGame/Sonic3|AndKnuckles}}'', which raises the question of why they didn't have him there from the start for inexperienced players. As a tradeback, you can't earn Achievements using Tails.
* PuzzleBoss: Many more compared to the rest of the series; while most of the bosses are of the "hit until he's dead" variety, all of them except the first (and, eventually, the last, which gets progressively easier to hit as the battle progresses) also require that you figure the "trick" to hurting them, from manipulative platforming to whittling down shields bit by bit.
* RefrainFromAssuming: "Sonic ~ You Can Do Anything", the opening theme song from the Japanese version, is often incorrectly cited as "Toot Toot Sonic Warrior" after part of the chorus, despite "you can do anything" actually being lyrics.
* ResetButton: The bad ending. Eggman presumably uses the Time Stones to CTRL-Z everything you did in the game.
* {{Sampling}}:
** The lyrics "Work that sucker to death! Come on, now! Work that sucker to death!" come from Xavier's song "Work That Sucker to Death". Worthy of note is that although the original song did say "work that sucker to death" often, this particular sample is only the chorus to the JP Sonic CD boss music.
** The Japanese soundtrack samples its opening and ending themes during normal gameplay, with the game over theme sampling the former (albeit slowed down and muffled) and the stage clear theme sampling the latter. Interestingly, both are intact in the 2011 remake despite the lyrics being cut from their sources.
* SanDimasTime: With all of the time-travel involved, the game still has the 10-minute-limit in its stages. Going to the past, or future (Good or {{Bad|Future}}), doesn't change this in the slightest.
* SaveThePrincess: According to the American manual for the Sega CD version, the pink hedgehog you are saving is actually [[WesternAnimation/SonicSatAM Princess Sally]], presumably to tie into the cartoon she hails from, despite Amy Rose (the hedgehog in question) looking nothing like the already established character.
* SaveScumming: The 2011 version of the game makes a save at the beginning of a Special Stage and doesn't save the results if the game is restarted before the results screen finishes. This makes it easier to get all seven Time Stones early, and doing it early enough would mean Quartz Quadrant Zone 2 and on automatically have good futures.
* SceneryPorn: The environments are beautiful to look at, possessing a dream like quality to them. This especially holds true for the Good Futures, a mix of technology and nature in bright flashy colors.
** SceneryGorn: The {{Bad Future}}s. Eggman's corruption hasn't been fixed, and the world has become a nightmarish dystopia. It's especially bad for the levels where water can been seen; the water ends up looking horribly polluted and nasty.
* ScienceIsBad: The Bad Futures, with all the broken machinery throughout them. Even Robotnik's MechaMooks and ''his own base'' are broken and rusted with neglected ruin.
** Inverted in the Good Futures, which also have a lot of machinery in them.
* SetRightWhatOnceWentWrong: Sonic's goal is to save the Little Planet's future by ridding it of Eggman's influence. He can achieve this by destroying the badnik generators in the past or collecting every Time Stone.
* ShoutOut: In the 2011 remake.
** The "[[Film/BackToTheFuture 88 Miles per Hour]]" achievement in the 2011 remake.
** The achievement for finishing any level in the Good Future is "[[ParadiseLost Paradise Found]]".
** The "King of the Rings" achievement is a call out to an old obscure Sonic song.
** DJ Eggman wears a [[BobMarley Jamaican]] headpiece on the Soundtrack Select screen.
* SlidingScaleOfShinyVersusGritty: The contrast between the good and bad futures.
* SmashingHallwayTrapsOfDoom: Real ones are found in Metallic Madness. Earlier, objects that look almost identical to these are found in Wacky Workbench, but they are completely harmless and actually drop you into secret areas if you [[ViolationOfCommonSense stand on them as they slam into the ceiling.]] [[GuideDangIt This is necessary to reach one of the Roboticizers.]]
* SoundtrackDissonance: The US boss theme ends up being this in the Good Futures. Wacky Workbench's Good Future also falls into this, having more emphasis on work tools in the background despite the zone being turned into a [[ToyTime toy land]].
* SpeedRun: The first game in the series to feature a Time Attack mode. This is also how you unlock some of the extras.
* StealthPun: The reason levels in this game are called Zones instead of Acts? [[WordOfGod That's because this game is (about)]] [[http://azukara.tumblr.com/post/24133187368/time-travels time travels.]][[note]] That is, "Palmtree Panic Time Zone 1", for example.[[/note]]
* TheSpiny: The Noro-Noro badnik will occasionally show spikes on its back. And Kemusi, found in the same level, is an expy of Caterkiller from Sonic 1.
* SteppingStonesInTheSky: In the intro movie, Sonic used the falling debris of the Little Planet as platforms to reach it.
* TakeThat: [[AllThereInTheManual The name of the first boss]] is the EGG-HVC-001. HVC-001 was the serial number name of Nintendo's own {{Famicom}} console, then Sega's rival company. As a bonus stealth insult, the HVC-001 [[WarmUpBoss is the easiest boss in the entire game.]]
* {{Tagline}}: The page quote.
* TechnoWreckage: The Bad Futures. Wacky Workbench and Metallic Madness especially.
* ThemeTuneCameo: "Sonic ~ You Can Do Anything" is an updated version of the Green Hills Zone music from the MasterSystem and GameGear versions of Sonic 2.
** Speaking of which, the Japanese GameOver theme actually samples the vocals from the chorus of "You Can Do Anything" (the "Toot Toot Sonic Warrior" part) and slows them down.
* TimeTravel: A present mechanic of the game, inspired by various books and films, including ''Film/BackToTheFuture''.
* ToyTime: Wacky Workbench's good future.
* TubeTravel: A lot of it in Metallic Madness Act 2.
* UnderwaterRuins: Tidal Tempest, though oddly not in the past (it's just a partially-submerged cave).
* UniqueEnemy: The Taga-Taga enemy found in Tidal Tempest also appears in Palmtree Panic, where it jumps out of waterfalls like Chopper from Sonic 1. PPZ's Taga-Taga is rare enough that you won't meet it [[EasterEgg unless you explore the levels.]]
* UnlockableContent: The remake. Special Stages in Time Attack, the D.A. Garden (The Incomplete Sound Test, plus a image of the Little Planet) and the Visual Mode (The Video Gallery).
* ViolationOfCommonSense: The fake SmashingHallwayTrapsOfDoom of Wacky Workbench. Standing on one will take you somewhere. [[spoiler:One is required to go to the roboticizer in Zone 1.]]
* WarmUpBoss: Palmtree Panic's boss, the EGG-HVC-001. It's a slow moving mini-mecha that can't even directly attack you; it's only defense is two arms with easily dodgeable Bumpers attached, and otherwise its only "attack" is inflicting collision damage, and it loses an arm with two of the three hits it takes to mow it down, which can be easily done in less than 15 seconds--or if you want to be even quicker, you can just move right behind the boss and attack it directly from behind as soon as it lands. On top of all that, due to an invincibility box at the beginning of the level, you can actually defeat the boss without being in any danger at all of being hurt. ''It's easier than [[VideoGame/SonicTheHedgehog2 The Drill-car.]]''
* AWinnerIsYou: The remake.
** Finish the game with the good ending, or watch the good ending through Visual Mode. A screen will show up telling you that "YOU ARE SUPER PLAYER", and Sonic, Amy and Metal Sonic will run across the screen from time to time.
*** This happened in the original too, not just the remake.
** The Tails ending in the remake is probably even more this trope because [[spoiler:all you get is some explosions and then a credits roll. You do not even get a congratulations. At the very least the credits for Tails are of the staff who worked on the remake but its still kind of disappointing.]]
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