| series = Sonic the Hedgehog

| platforms = Sega Genesis, Windows

| released =

| modes = Single-player

| genre = Platform

is a 1994 platform game developed by Sega Technical Institute and published by Sega for the Sega Genesis. Players control Sonic the Hedgehog or Knuckles the Echidna in their quests to save Angel Island; Sonic tries to stop Doctor Robotnik from re-launching his orbital weapon, the Death Egg, while Knuckles scuffles with Robotnik's minion, EggRobo. Like previous Sonic games, players traverse side-scrolling levels at high speeds while collecting rings and defeating enemies.

Sega Technical Institute developed Sonic & Knuckles simultaneously alongside its predecessor, Sonic the Hedgehog 3 (1994); they were planned as a single game until time constraints and cartridge costs forced the developers to split it. The Sonic & Knuckles cartridge features an adapter that allows players to connect the Sonic the Hedgehog 3 cartridge, creating a combined game, Sonic 3 & Knuckles. Sonic the Hedgehog 2 (1992) can also be attached, allowing players to control Knuckles in Sonic 2 stages. Attaching the original Sonic the Hedgehog or any other Genesis game released prior to this will unlock the "Blue Sphere" minigame.

Sonic & Knuckles was released for the Sega Genesis on October 18, 1994. It received positive reviews; critics were impressed with the replay value and lock-on technology, despite its similarity to Sonic 3. The games sold a combined four million copies worldwide, placing them among the best-selling Sega Genesis games. They have since been rereleased in various Sega and Sonic compilations.

Gameplay

thumb|left|Knuckles explores Mushroom Hill, the first zone of Sonic & Knuckles.

Since Sonic & Knuckles and Sonic the Hedgehog 3 were initially developed as one game, their gameplay is similar: both are 2D side-scrolling platformers with similar level design, graphics, and game mechanics. However, in Sonic & Knuckles, unlike in Sonic 3, the player chooses either Sonic or Knuckles at the title screen, The first act of each level ends with a miniboss fight with one of Dr. Robotnik's robots, while the second ends with a regular boss fight with Robotnik (or EggRobo in Knuckles's campaign). Sonic and Knuckles traverse levels differently; Sonic can jump higher and has access to unique shield abilities, whereas Knuckles can glide and climb most walls. The levels also include cutscenes that differ based on the character selected, as Sonic and Knuckles are opponents for most of the game.

Special Stages are entered by finding giant rings hidden in secret passageways: the player is placed in a 3D environment and must turn all of a number of blue spheres red by running through them, but must avoid all red spheres, including formerly blue ones. Yellow spheres bounce the player long distances, and white spheres with red stars on them make the player walk backward in the opposite direction. Completing a Special Stage earns the player a Chaos Emerald; collecting all seven Emeralds allows the player to turn into Super Sonic or Super Knuckles, more powerful versions of the characters. the ability to play through Sonic 3 levels as Knuckles Additionally, combining the cartridges is the only way to collect "Super Emeralds", earned by accessing Special Stages in the Sonic & Knuckles levels after collecting all seven Chaos Emeralds from Sonic 3. When all Super Emeralds have been collected, Sonic, Knuckles, and Tails can transform into Hyper Sonic, Hyper Knuckles, and Super Tails, each with unique abilities.

Inserting Sonic 2 unlocks Knuckles the Echidna in Sonic the Hedgehog 2, wherein the player can play Sonic 2 using Knuckles's abilities. From here, the player can also access a minigame based on Sonic 3 and Sonic & Knuckles Chaos Emerald Special Stages. Sonic 3 and Sonic & Knuckles were originally planned as a single game; according to designer Takashi Iizuka, the team "really wanted to hit a home run", with larger stages that took longer to develop. Sonic 3 was split in two, with Sonic & Knuckles as the second part. As Mushroom Hill became the first stage of Sonic & Knuckles, the developers lowered its difficulty.

Despite the split, the developers wanted the games to feel like a single experience.

The team explained their situation to Sega's hardware division, which gave them the lock-on adapter. The team knew that players would likely use the adapter to insert games beside Sonic 3, so they implemented the Blue Sphere minigame for most games. They made Knuckles playable in Sonic 2 if that game was inserted because the team found his play style suited its levels. They considered including the same functionality for the original Sonic the Hedgehog, but the developers felt Knuckles's abilities did not work with its level design. It was released around the same time as Nintendo's Donkey Kong Country for the Genesis's competitor, the Super Nintendo Entertainment System. Industry figures called the coinciding releases a "battle" as both advertised "revolutionary" technological advances: lock-on technology for Sonic & Knuckles and 3D-rendered graphics for Donkey Kong.

Sonic & Knuckles was backed by a $45 million marketing campaign; at the time, video games typically had a marketing budget of $5 million. MTV broadcast the tournament finale along with footage of the game as MTV's Rock the Rock. Sonic & Knuckles Collection (1997) and Sonic & Garfield Pack (1999) for the PC, Sonic Mega Collection (2002) for the GameCube; Sonic Mega Collection Plus (2004) for the PlayStation 2, Xbox, and PC; Sonic's Ultimate Genesis Collection (2009) for the Xbox 360 and PlayStation 3; and Sonic Classic Collection (2010) for the Nintendo DS.

Sonic Jam, in addition to featuring the original release, included some new "remix" options to modify the game: "Normal" mode alters the layout of rings and hazards and "Easy" mode removes certain acts entirely from the game. The version in Sonic's Ultimate Genesis Collection does not retain the lock-on feature included in other versions of the game, because of "tight development times".

The game has been re-released through the Wii's Virtual Console and Xbox 360's Xbox Live Arcade. Both releases are programmed such that, if any of the "Lock-on" games are also downloaded on the same account, the "connected" versions of the game are also available. For example, if one downloads Sonic & Knuckles and Sonic 2, they have the option to play the corresponding Knuckles in Sonic 2 game.

Sonic & Knuckles is included in the retro console Sega Genesis Flashback released in 2017 by AtGames, a compilation of 45 Genesis games that does not have Sonic 3.

Sonic 3 & Knuckles was re-released for the first time since 2011 as part of the Sonic Origins compilation in 2022. All versions of the games included in Origins are remasters running on the Retro Engine, with Sonic 1, 2 and CD being new ports of existing remasters. This version of the title was developed by Simon Thomley of Headcannon, who previously worked on both Sonic Mania and the other titles included. The Origins version features the original "Blue Sphere" minigame as a bonus mode, as well as new iteration of the mode called "New Blue Spheres" which includes the additional sphere colors introduced in Sonic Mania.

Reception

The Genesis version sold at least 1.24 million copies in the United States. Sonic 3 and Sonic & Knuckles sold a combined cartridges worldwide.

Critics praised Sonic & Knuckles, despite its similarity to its predecessor. The four reviewers of Electronic Gaming Monthly named it their "Game of the Month". They lauded the lock-on technology and remarked that despite that being "more of the same, it still is an exceptional game". Next Generation remarked, "Basically, this is the same Sonic game that Sega has sold for the last three years, just wrapped up better and with a prettier ribbon."

Critics praised the lock-on technology the game offered. Lucas Thomas of IGN said it was "a great game on its own", but the lock-on feature completely revamped the overall experience. stating that he could not fully appreciate its predecessor without its "companion piece". Sega Power review praised the game's harder difficulty in comparison to its predecessor and the new expansion of levels, admitting that the expansion would not have been possible had Sonic 3 been a single game. Sega Magazine review similarly praised the lock-on technology and the new innovation the unique cartridge offered, adding that Sonic & Knuckles hidden stages and bosses would strongly add to the replay value of the combined game. A remake of the Sky Sanctuary stage was made for the Xbox 360, PlayStation 3, and PC versions of the game, while the Mushroom Hill level was remade for the Nintendo 3DS version of the game. Sonic & Sega All-Stars Racing features a track inspired by the Death Egg as downloadable content along with the Metal Sonic character. Re-imagined versions of the Flying Battery and Lava Reef stages, along with the Blue Sphere bonus game, appear in the 2017 game Sonic Mania. Sonic the Hedgehog 2 draws inspiration from Sonic & Knuckles, though it is not a direct adaptation.

In 2022, 30 years after the release of the game, Paramount announced the release of the film Sonic the Hedgehog 3 in December 2024, as well as the release of Knuckles on Paramount+ in April of that year; the creative team behind the live-action franchise confirmed this was meant to be an homage to the Sonic the Hedgehog 3/Sonic & Knuckles double-feature.

Notes

References

Works cited

  • Official Virtual Console website