History VideoGame / SonicTheHedgehog1

* NintendoHard: Compared to most other games in the series, this game is quite difficult. It revolves around the player's ability to gain and control [[WreakingHavok Sonic's momentum]] well enough to avoid or overcome various obstacles, many of which can [[OneHitKill kill Sonic instantly regardless of rings]]. The momentum can be surprisingly hard to get because his moves are very limited compared to the various speed-boosting skills he has in later games like the Spin Dash, Super Peel-Out, and Drop Dash. Additionally, the Special Stages [[SuddenGameplayChange play very differently than the rest of the game]] and are [[AlienGeometries deliberately confusing to the eyes and difficult to navigate]].

-->-- Magazine Ad for the game.

** There are a few zones with rather bland one word names (Marble, Labyrinth, Final), whereas every subsequent 2D ''Sonic'' game would either give the zones two word names or one big word as a name.

Released on June 23, 1991 for the UsefulNotes/SegaGenesis, it marked the beginning of Creator/{{Sega}}'s beloved ''Franchise/SonicTheHedgehog'' franchise and is one of the most iconic games of the [[UsefulNotes/The16bitEraOfConsoleVideoGames 16-bit era]]. An [[VideoGame/SonicTheHedgehog18Bit 8-bit Master System / Game Gear counterpart]] was also released in 1991.

It practically re-defined the [[PlatformGame platforming genre]] by adding branching paths and [[WreakingHavok physics-based obstacles]] such as loops and slopes. In addition to the touted high-speed gameplay, gamers of the time were astonished by the impressive graphics, as well as the catchy soundtrack by Masato Nakamura of the Japanese pop group, Dreams Come True. ''Sonic the Hedgehog'' put the Genesis on the map and was a catalyst for the console temporarily dethroning [[Creator/{{Nintendo}} The Big N]] with a 65% market share over the [[UsefulNotes/SuperNintendoEntertainmentSystem Super NES]] during the 16-bit UsefulNotes/ConsoleWars, at least outside of Japan. This was by far the best-selling game for the Genesis/Mega Drive with over 15 million units sold worldwide.

** Sega's U.S. marketing department had Dr. Eggman changed to Dr. Ivo Robotnik for the Western release. They're also the ones who coined "Badnik" for his MechaMooks, which were just called "Eggman robots" in Japanese. As of the [[UsefulNotes/SegaDreamcast Dreamcast]] era, Yuji Naka has stated that [[RetCanon Eggman is his nickname or alias, while Robotnik is his actual name]]. This is reaffirmed by his relatives' surnames, as well as numerous references throughout the series.

** The [[SpinAttack Spin Dash]] doesn't exist in the original Genesis version. Various ports of the game added an option to use it: ''VideoGame/SonicJam'' for the UsefulNotes/SegaSaturn, ''Sonic the Hedgehog Genesis'' for the UsefulNotes/GameBoyAdvance, the M2 version for UsefulNotes/Nintendo3DS and UsefulNotes/NintendoSwitch, and the 2013 remastered version.

* ScreenCrunch: ''Sonic the Hedgehog Genesis'' for the Game Boy Advance -- which has been criticized for being a very sloppy port of the game -- must have hit some sort of zenith, with this trope being responsible for the port's massive slowdown problems as the original game's assets were haphazardly imported into the ''[[VideoGame/SonicAdvanceTrilogy Sonic Advance]]'' engine with no regard whatsoever for the engine's art size limits. The result? The engine chokes while trying to deal with the massive sprites due to crunching the game's original resolution from 320x224 on the Genesis to a pitiful 240x160 screen on the Game Boy Advance.

** ''Sonic the Hedgehog Genesis'' for the Game Boy Advance ''tried'' to include features such as a save system and the Spin Dash, but due to the game being hastily ported into the engine used by ''VideoGame/{{Sonic Advance|Trilogy}}'' for Sonic's 15th anniversary, it also introduced many problems and game-breaking bugs the original game or prior re-releases never had.