History VideoGame / Sonic3DIn2D

* NintendoHard: Compared to the original 2D games, this game is quite difficult. Bosses are much more aggressive than usual, for example.

The game allows you to play as Sonic, Tails and Knuckles, along with 5 unlockable characters. It has the full original soundtrack of the Mega Drive/Genesis version of the game along with an additional DLC that adds the soundtrack of the Sega Saturn version and the ability to play customized music. 23 Achievements can also be obtained as additional challenge for the game.

* AdaptedOut: the actual invincibility theme from the original game's Sega Genesis soundtrack is replaced with the one from ''[[VideoGame/Sonic3AndKnuckles Sonic & Knuckles]]'', since Sotaknuck thought it was a much better fit. The Invincibility theme (albeit it being the Worlds Delta remixed version) is used for the Speed Shoes instead.

* AmusementParkOfDoom: Spring Stadium. Balloons, bumpers, springs, and spikes that emerge out of from the ground!
* ArcWelding: Eggman's outfit has the arm-stripes as seen on his modern design, a mural of Perfect Chaos can be found in Rusty Ruins Act 2, and the boss of Diamond Dust Act 1 is E-99, who resembles a hybrid of an Eggrobo and E-102 Gamma. [[spoiler: Furthermore, the Final Weapon's design is a recreation of the final boss from ''Sonic Pocket Adventure'', itself meant to be an ArcWelding storyline that added modern elements into a Classic game, with its most notable scene midway into the game being walking in on Eggman thinking about how his ''Adventure'' era outfit looks on him.]]

* ATasteOfPower: You start the game with all seven Chaos Emeralds already in your possession...until Robotnik and Silver Sonic take them off your hands.

* ArcWelding: Eggman's outfit has the arm-stripes as seen on his modern design, a mural of Perfect Chaos can be found in Rusty Ruins Act 2, and the boss of Diamond Dust Act 1 is E-99, who resembles a hybrid of an Eggrobo and E-102 Gamma.

* Infinite1Ups: Rings and 1-up monitors respawn after doing a Special Stage, allowing lives to be rapidly racked up in the more backtracking-friendly levels if you know your way around.

* AdaptatedOut: the actual invincibility theme from the original game's Sega Genesis soundtrack is replaced with the one from ''[[VideoGame/Sonic3AndKnuckles Sonic & Knuckles]]'', since Sotaknuck thought it was a much better fit. The Invincibility theme (albeit it being the Worlds Delta remixed version) is used for the Speed Shoes instead.

* AdaptatedOut: For some unknown reason, the actual invincibility theme from the original game's Sega Genesis soundtrack is replaced with the one from ''[[VideoGame/Sonic3AndKnuckles Sonic & Knuckles]]''.

The game tries to answer the question "what if it never left the 2D formula?" and rebuilds the original plot by adding in additional elements (like ACT 1 bosses), trying to make the game feel like the bridge game between ''VideoGame/Sonic3AndKnuckles'' and ''VideoGame/SonicAdventure''.

After the events of ''Sonic 3 & Knuckles'', Robotnik finds out about the hidden power of the birds that inhabit Flicky's Island. Those mysterious birds can travel through dimensions using large gold rings. Determined to harness their power for his own gain, the evil scientist sets off for the island with a new plan... The game allows you to play as Sonic, Tails and Knuckles, along with 5 unlockable characters. It has the full original soundtrack of the Mega Drive/Genesis version of the game along with an additional DLC that adds the soundtrack of the Sega Saturn Version and the ability to play customized music. 23 Achievements can also be obtained as additional challenge for the game.

* ActionBomb: The Snowbomb badniks in Diamond Dust Zone explode after a few seconds if you get too close.

* BonusStageCollectables: The Chaos Emeralds as usual can be obtained via Special Stages, modeled after those from ''VideoGame/SonicTheHedgehog2'' and the Saturn version of Sonic 3D. Two of them can be also obtained from the first two ACT 1 bosses.

* BottomlessPitRescueService: Tails or [[spoiler:Wechnia]] will rush to pick the player should they fall off-screen during the Panic Puppet Zone ACT 1 Boss Phase.
* BottomlessPits: Almost none, actually, with notably one as a stage hazard during the boss in Gene Gadget ACT 2.

* CutsceneIncompetence: Present in Green Grove ACT 1.

** [[spoiler:Wacky Workbench's mysterious statue, a Chaos Mural and the Profecy Mural from ''Sonic 3 & Knuckles'' all appear somewhere in the Rusty Ruins, not to mention all of the unlockable characters and the extra scene in the Good Ending.]]
** As of Version 1.23, getting the Good Ending adds a secret switch somewhere in Gene Gadget ACT 1 that changes the boss for the act. [[spoiler:Instead of fighting just a random selection of three of the Sonic robots, you fight all five in sequence.]]

* EvilKnockoff: [[spoiler:Tails Doll]] and [[spoiler:Mecha Knuckles]] return from ''VideoGame/SonicR'' as well as [[spoiler:all of Sonic's robotic Doppelgangers]].
* EverythingTryingToKillYou: Gene Gadget Zone is a prime example of this. Mines, badniks, and electrical fields are everywhere. Panic Puppet Zone also adds circular saws into the mix.

* GlitchEntity: Now playable. [[spoiler:Bluckles, Ashura, and Wechnia, the famous glitch characters from ''Sonic 2'', ''Sonic 3 & Knuckles'', and ''VideoGame/KnucklesChaotix'']], are unlockable and promoted to fully playable characters with their own unique movesets.

* HighAltitudeBattle: Panic Puppet Zone ACT 1 Boss. [[spoiler:This is the last battle with the Eggmobile, and Robotnik really wants you to fail, putting Sonic where his speed doesn't matter.]]

* InconvenientlyPlacedConveyorBelt: In the boss area for Gene Gadget Zone ACT 2, it will lead you to your death. Also, a lot of them in Panic Puppet Zone actively push you backward or straight into an obstacle.

* MarathonLevel: Panic Puppet Zone ACT 1 is particularly long. Adding to it is a two-phase boss that can easily bring a player into time over territory.

* RecurringRiff: ACT 1 and ACT 2 remix the themes. Panic Puppet Zone in the Mega Drive/Genesis Soundtrack is an exception, though.

** The Mega Drive/Genesis soundtrack uses music from ''VideoGame/Sonic3AndKnuckles'' that the original game didn't already use, plus the default "Speed Up" and "Drowning" themes in the Sonic Worlds engine, and the ''Sonic 3 Complete'' version of the unused theme from the ''Sonic 3'' prototype.
** The Saturn soundtrack uses music from ''VideoGame/SonicTheHedgehogCD'' (both the US and JP/EU versions), ''VideoGame/SonicR'', and ''VideoGame/MetropolisStreetRacer''.
* RiseToTheChallenge: The first phase of Volcano Valley ACT 1 boss, where the player has to survive the lava rising up in a caldera.
* ScaryScorpions: A new version of the Skorp badnik returns in Volcano Valley with a different tail attack.

* SequentialBoss: for Gene Gadget ACT 1 and Panic Puppet ACT 1.

* ShoutOut: The first phase of Panic Puppet ACT 1 boss shares elements with the first phase of ''Rocket Knight Adventures''[='=]s FinalBoss.

* TheStinger: Beat the game without collecting all the Chaos Emeralds, and Robotnik will laugh in front of his final weapon, gloating about his victory. Get them all, and you'll witness a teaser for Sonic Adventure.

* UnwillingRoboticization: Robotnik's Badniks, that in this occasion are exclusively Flicky Powered.
* WakeUpCallBoss: Right at the end of Green Grove ACT 2, the boss will test the player's knowledge of the character's skills and their spacing ability to dodge a huge bouncing spike ball.

After the events of ''Sonic 3 & Knuckles'', Robotnik finds out about the hidden power of the birds that inhabit Flicky's Island. Those mysterious birds can travel through dimensions using large gold rings. Determined to harness their power for his own gain, the evil scientist sets off for the island with a new plan... The game allows you to play as Sonic, Tails and Knuckles, along with 5 unlockable characters. It has the full original soundtrack of the Mega Drive/Genesis version of the game along with an additional DLC that adds the Sountrack of the Sega Saturn Version and the ability to play customized music. 23 Achievements can also be obtained as additional challenge for the game.

* EasterEgg: Plenty. [[spoiler:Wacky Workbench's mysterious statue, a Chaos Mural and the Profecy Mural from ''Sonic 3 & Knuckles'' all appear somewhere in the Rusty Ruins, not to mention all of the unlockable characters and the extra scene in the Good Ending.]]

* CutsceneIncompetence: in Green Grove ACT 1.

* DoubleJump: the Electric Shield allows Sonic to double jump.

* EverythingTryingToKillYou: Gene Gadget Zone is a prime example of this. Mines, badnicks and electrical fields are everywhere. Panic Puppet Zone also adds circular saws into to the mix.

* GiantMecha: The Final Weapon built by Robotnik
* GlitchEntity: now playable. [[spoiler:Bluckles, Ashura and Wechnia, the famous glitch characters from Sonic 2, Sonic 3 & Knuckles and Knuckles Chaotix]] are unlockable and promoted to fully playable characters with their own unique movesets.

* GreenRocks: The Chaos Emeralds
* GroundPound: A move in the arsenal of [[spoiler:Shadow]] and [[spoiler:Bluckles]], as well as used against the player by [[spoiler:Mecha Knuckles]]
* HarmlessFreezing: without a water shield the player can be encased in ice in Diamond Dust Zone. They will lose a shield, but they will be invincible as long as they stay frozen and don't slide on spikes.
* HighAltitudeBattle: Panic Puppet Zone ACT 1 Boss. [[spoiler: This is the last battle with the Eggmobile, and Robotnik really wants you to fail, putting Sonic where his speed doesn't matter.]]
* HellIsThatNoise: the infamous drowning theme that plays when you're running out of air.
* IdleAnimation: a staple of the series. Leave the characters without any action and they'll get quickly get bored.
* InconvenientlyPlacedConveyorBelt: In the boss area for Gene Gadget Zone ACT 2 it will lead you to your death. Also a lot of them in Panic Puppet Zone actively push you backward or streight into an obstacle.

* MarathonLevel: Panic Puppet Zone ACT 1 is particularly long. Adding to it is a two phase boss that can easily bring a player into time over territory.

* MultipleEndings: just like the original, there are two endings in the game. The bad ending without all of the Chaos Emeralds, and the good one with all the gems collected.
* MutuallyExclusivePowerups: any of the five shields. Getting a new shield cancels the held one out.
* NintendoHard: compared to the original 2D games, this game is quite difficult. Bosses are much more aggressive than usual, for example.
* NoFinalBossForYou: unless you collect all the Chaos Emeralds, you won't be able to access The Final Fight.
* NoSell: the three elemental Shields make the user immune to traps and enemies that use those elements. Additionally the Water Shield allows the user to breathe underwater.
* PainfulPointyPufferfish: the floating Spikefishes in Spring Stadium Zone.
* PaletteSwap: [[spoiler:Bluckles, Ashura and Wechnia]] but they come with their own movesets. An unlockable option also allows to literally swap Knuckles' palette with his cutscene one from Sonic 3.

* RecurringRiff: ACT 1 and ACT 2 remix the themes. Panic Puppet Zone in the Mega Drive/Genesis Soundtrack is an exception though.
* RiseToTheChallenge: the first phase of Volcano Valley ACT 1 boss where the player has to survive the lava rising up in a caldera.
* ScaryScorpions: a new version of the Skorp badnik returns in Volcano Valley with a different tail attack.
* SequelHook: get a good ending to witness it.

* SpringsSpringsEverywhere: some sections in the level require the player to jump through a series of springs to move forward. Spring Stadium Zone, as the name implies is literally filled with springs, even if a lot of them are fake ones just like in the original game.
* SuperMode: the character's Super form is playable once all the Chaos Emeralds have been collected. [[spoiler: Amy cannot transform until all Achievements are obtained, and that is enabled only in a cleared gamefile to preserve her status as the hard mode of the game should the player start a new game with her.]]
* ShoutOut: The first phase of Panic Puppet ACT 1 boss shares elements with the first phase of Rocket Knight Adventures's Final Boss.
* SpikesOfDoom: many, especially in Spring Stadium.
* SprintShoes: smash a Speed Shoes monitor and temporarily get a speed boost.
* TempleOfDoom: Rusty Ruins Zone is an abandoned ancient ruin with green vines and grass taking over. Its traps are still perfectly functional though.

* TimedMission: the 10 minute timer missing in the original 3DBlast returns from 3K.
* TubeTravel: first present in a small sections of Green Grove and Rusty Rusty, pipes become more prominent in Volcano Valley and will become the main gimmick of Gene Gadget Zone with pipe puzzles that homage Sonic 2 for Sega Master System.

* UnderwaterRuins: part of Rusty Ruins Zone is submerged in water.

* WakeUpCallBoss: right at the end of Green Grove ACT 2 the boss will test the player's knowledge of the character's skills and their spacing ability to dodge a huge bouncing spike ball.
* WeaponizedExhaust: If the boss uses a rocket to fly, it can use that rocket to hurt you. If you have a Flame Shield you're unaffected by the exhaust though.

After the events of Sonic 3 & Knuckles, Robotnik finds out about the hidden power of the birds that inhabit Flicky's Island.
Those mysterious birds can travel through dimensions using large gold rings. Determined to harness their power for his own gain, the evil scientist sets off for the island with a new plan...
The game allows you to play as Sonic, Tails and Knuckles, along with 5 unlockable characters.
It has the full original soundtrack of the Mega Drive/Genesis version of the game along with an additional DLC that adds the Sountrack of the Sega Saturn Version and the ability to play customized music.
23 Achievements can also be obtained as additional challenge for the game.

* HundredPercentCompletion: get all the 23 Achievements and [[spoiler:unlock Super Amy to use in a cleared save file]]
* ActionBomb: the Snowbomb badniks in Diamond Dust Zone explode after a few seconds if you get too close.

* AmusementParkOfDoom: Spring Stadium. Balloons, bumpers, springs and spikes that emerge out of from the ground!

* BecauseDestinySaysSo: Not only the mural from Hidden Palace can be spotted in Rusty Ruins, but also a mural of Chaos and, for real explorers also a mural of the Final Weapon lies somewhere in the game.

* BookEnds: The game starts with Sonic Tails and Knuckles arriving on Flicky Island and ends with them leaving it. When an Extra character is unlocked they will appear from a large ring, and leave the game from one in the ending.
* BossOnlyLevel: The Final Fight. The entire zone consists of a two stages boss battle.
* BottomlessPitRescueService: Tails or [[spoiler:Wechnia]] will rush to pick the player should they fall off screen during the Panic Puppet Zone ACT 1 Boss Phase.
* BottomlessPits: almost none actually, with notably one as a stage hazard during the boss in Gene Gadget ACT 2.

* DifficultButAwesome: Sonic's Insta-Shield. Increases the range at which you can hurt enemies, and allows you to deflect projectiles and hit through spikes of enemies. It only lasts a split second, though, so good timing is an absolute must. It usage also reactivates air control, which can make a difference while platforming.

* EasterEgg: Plenty. [[spoiler:Wacky Workbench's mysterious statue, a Chaos Mural and the Profecy Mural from Sonic 3 & Knuckles all appear somewhere in the Rusty Ruins, not to mention all of the unlockable characters and the extra scene in the Good Ending]].

* EvilKnockoff: [[spoiler:Tails Doll]] and [[spoiler:Mecha Knuckles]] return from Sonic R as well as [[spoiler:all of Sonic's robotic Doppelgangers]].

* No-Sell: the three elemental Shields make the user immune to traps and enemies that use those elements. Additionally the Water Shield allows the user to breathe underwater.

* HundredPercentCompletion: get all the 23 Achievements and [[Spoiler:unlock Super Amy to use in a cleared save file]]

* Easter Egg: Plenty. [[spoiler:Wacky Workbench's mysterious statue, a Chaos Mural and the Profecy Mural from Sonic 3 & Knuckles all appear somewhere in the Rusty Ruins, not to mention all of the unlockable characters and the extra scene in the Good Ending]].

* PaletteSwap: [[spoiler:Bluckles, Ashura and Wechnia]] but they come with their own movesets. An unlockable option also allows to select Knuckles' alternate color palette from Sonic 3.

* ThatOneBoss: Robotnik in Panic Puppet Zone ACT 1. Not only you're fighting hanging in the sky with reduced mobility, but Eggman will relentlessly charge at you and throw detachable drills in your direction.

''Sonic 3D in 2D'' is a 2020 reimagining of ''VideoGame/Sonic3DFlickiesIsland'', a fan game created by [=Sotaknuck=] built with Multimedia Fusion 2.5 and version 1.5.1 of the Sonic Worlds engine.

The game tries to answer the question "what if it never left the 2D formula?" and rebuilds the original plot by adding in additional elements, trying to make the game feel like the bridge game between ''VideoGame/Sonic3AndKnuckles'' and ''VideoGame/SonicAdventure''.

The mysterious birds can travel through dimensions using large gold rings. Determined to harness their power for his own gain, the evil scientist sets off for the island with a new plan...

* PaletteSwap: [[spoiler:Bluckles, Ashura and Wechnia]] but they come with their own movesets.

* SuperMode: the character's Super form is playable once all the Chaos Emeralds have been collected. [[spoiler: Amy cannot transform until all Achievements are obtained, and only in a cleared gamefile.]]

* TheMaze: Rusty Ruin Zone.
* TheVeryDefinitelyFinalDungeon: The Final Fight.