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Knuckles' Chaotix, in Japan called simply Chaotix, is a platform game in the Sonic the Hedgehog series, developed by Sega of Japan rather than Sonic Team, and published by Sega for the Sega 32X. The game was released in North America in March 1995, in Japan on April 21, 1995 and finally in Europe in May 1995. Despite demand from fans, the game's only "re-release" has been through GameTap's PC service. It was originally going to be in Sonic Gems Collection but it was not included for unknown reasons. (Possibly emulation issues) However, an entire section of the museum of Sonic Gems Collection is dedicated to this game. It is the only Sonic-related game to be released for the Sega 32X and its stand out features include its 2D sprite-based graphics and simultaneous two player gameplay.
The main story of the game as taken from the western manual:
Tomorrow's the big opening day for Carnival Island, a huge amusement resort with the latest in high-tech rides and games. As guardian of the island, it's Knuckles' job to make sure nothing goes wrong before the grand event.
Unfortunately, the evil Dr. Robotnik has other plans. He needs fuel for his latest diabolical device, and the Power Emerald that supplies electricity to the entire island fits the bill perfectly. His awful new invention, the Combi Confiner, should help him get rid of that annoying echidna and his friends.
When Knuckles returns from patrolling the far end of the island, he discovers that Dr. Robotnik has imprisoned all of his friends- Espio the Chameleon, Mighty the Armadillo, Vector the Crocodile and Charmy Bee. After he chases the Doctor off, Knuckles discovers that he can rescue one friend at a time by using Ring Power... only the power that sparks between the rings holds the two partners together like a magical rubber band. Never held back for long, Knuckles finds that with a little teamwork, he can use the stretching and snapping action of the Ring Power to double- even triple- the partners' speed.
And they need all the speed they can get. As Dr. Robotnik drains the power from Carnival Island, everything on the island begins to break down! Robotnik must be stopped, or by tomorrow morning - the morning of Carnival Island's big opening day - the grand amusement park will lie in ruins!
The story was completely different according to the Japanese manual. In it, a mysterious island rose from the sea shortly after the events of Sonic & Knuckles. Dr. Eggman discovered the island, and found a mysterious ring inscribed with descriptions of the Chaos Rings, ancient Rings infused with Chaos Emerald energy. In order to find these Rings, Eggman built his base, the Newtrogic High Zone, on the island. Mighty the Armadillo, Espio the Chameleon, Vector the Crocodile, and Charmy Bee also arrived at the island, and ended up being captured by Eggman and Metal Sonic, and placed in Eggman's Combi Catcher machine. Knuckles, curious about the strange island, goes there as well, and manages to rescue Espio. The two then go on to stop Eggman from getting the Chaos Rings.
Knuckles' Chaotix marks the debut of the Chaotix. The group has five members, including Knuckles the Echidna. The other four characters were headed up with Mighty the Armadillo (who also featured in the arcade game SegaSonic the Hedgehog two years earlier in 1993) and also featured Vector the Crocodile, Espio the Chameleon and Charmy Bee. These characters were from Team Chaotix. It also included Heavy and Bomb. Vector and Charmy did not return (with the exception of Espio, who appears as one of the playable characters in Sonic the Fighters a year later) until Sonic Heroes in 2004.
Each character in Knuckles' Chaotix has his own special abilities. Knuckles still glides and climbs as he did in Sonic & Knuckles. Espio has the ability to walk upright on walls and ceilings, and instead of curling up into a ball when performing the spin dash, he twists into a tornado, and can destroy unguarded enemies by running headlong into them at full speed. Mighty is the fastest runner in the game, and he has the ability to scale walls with his feet and push himself upward. Vector is the largest member of Chaotix. His moves include a mid-air dash and the ability to climb on walls. Charmy, finally, is the smallest character in the game but his ability to fly gives him a definite edge over the other characters.
Aside from Knuckles and his friends, the game also introduces Heavy & Bomb, two robots who claim to have escaped from Dr. Robotnik's evil clutches, and want to help team Chaotix. Heavy & Bomb cannot be selected from the character select screen, but instead are picked up through the combi catcher. Neither of the two robots can attack. Just as his name says, Heavy is heavy and slow, yet he is indestructible and has the ability to destroy enemies and monitors by simply walking against them. Bomb on the other hand is tiny and quick, but he explodes when he's hit, hurting friend and foe alike. Both of these characters can only be playable directly if the Stage Select is activated through the game's Color Test. They can also be played as normally in Special Stages if the player has one of them as their partner and throws them into the Special Stage ring.
The primary objective of the game remains unchanged from previous Sonic titles. The player must finish each level in under ten minutes and defeat Dr. Robotnik's badniks along the way. Rings still constitute the player's life energy and can be collected to enter special stages. Extra lives are unobtainable in the game-once the player is damaged when he has no rings and his partner is absent (if you have no rings, getting hit will temporarily cause you to lose your partner, but he will return eventually-effectively making your partner an 'extra hit point' for the players sake) or if you use 'recall' to reduce your ring counter to negative 99 rings or lower, you will automatically be taken back to the world lobby (or back to the title screen, if you are in Isolated Island when this happens, which is also only possible through using recall, due to lack of hazardous obstacles or enemies in that level) and be given a chance to leave/save or to choose a different partner and/or try to choose another attraction to play.
The levels are divided into five worlds (called "attractions" in the game), each one consisting of five different levels in which every two stages/acts played, change to a specific time of the day (morning, day, sunset, and night). The time of day effects enemy placements and boss difficulty. At the end of Level 5, the player confronts Dr. Robotnik in one of his contraptions.
The most fundamental change in Knuckles' Chaotix (and what eventually became one of the most criticized features of the game) involves the special ring force bond between characters. In earlier Sonic games, two-player mode would consist either of a traditional split screen race or a joint single player effort with Tails as a secondary character. In the latter case, this meant that Tails could move off screen and get lost for a few seconds until he returned to Sonic.
In Knuckles' Chaotix however, both players are at all times connected on one single screen while neither player acts as the dominant force to move the game forward. Besides the staple of traditional Sonic moves and individual abilities this means some new tricks can be executed with the elastic force of the ring bond. For example, player 1 can hold his position while player 2 runs forward and stretches the bond to gain maximum speed. In mid-air the bond can be used to generate an upward momentum. Additionally, players can toss each other toward platforms or use the call-button to reunite (at a cost of ten rings, which meant that for the first and only time the ring count could dip below zero in a Sonic game). Also, in two player mode if either player is hit without a shield/invincibility/big ring (a item that when obtained, causes you to lose all of your rings in the form of one, slightly larger than usual ring temporarily if you are hit) they lose all of their rings (which is not the case in single player mode, when if the partner is hit, he only loses one ring instead of all of them).
Recently, some elements of the game have received new life with Espio, Vector, and Charmy returning to the series as of Sonic Heroes. Also, the concept of a player controlling two characters is reused for Sonic Advance 3.
Due to the game being much longer than most Sonic games at the time, the game was given a battery-backup save feature which allowed the player to save their progress either manually (by going past the exit sign) or automatically (your progress is immediately saved after you beat an act/special stage).
On a side note, all of the badniks and almost all of the bosses in the game use gray, power sapped rings to function rather than animals. However, the rings cannot be collected like regular rings, as they dissolve not long after falling out of their badnik/boss machine. This concept was later used for Sonic Advance 3's robots, but the rings appear to be fine when released and can be collected like any other ring.
- Isolated Island/Practice Stage: A special isolated area played before the main game to get players acquainted with the special unique maneuvers introduced into the game. There are also no enemies/obstacles to hinder your progress, making this the easiest and shortest 'attraction' in the entire game.
- Botanic Base: The island's most natural attraction is this giant greenhouse, filled with oddly geometric trees, and a jungle of hostile flora-based badniks.
- Speed Slider: A rollercoaster reminiscent of Casino Night and Carnival Night Zone, Speed Slider is the fastest attraction in Knuckles' Chaotix. The level moves all the way to a confrontation with Dr. Robotnik on his carousel. Also, midway in all of the acts a fully 3-D platform that slowly rises but quickly falls can be found and used to access a different part of the stage (also, depending on which part of the platform the player is standing on, the view-point of the platform is altered, possibly to create a 3D illusion in a 2D game).
- Amazing Arena: This is the only stage in the game that has an extra requirement that must be fulfilled before the goal in each act is reached. At the start of each act in this stage, the scenery is primarily gray and the music is slow, but once the player finds and turns on a lightswitch, Amazing Arena turns bright and colourful and the music becomes active and cheerful. However, if the player reaches the goal sign in an act without first finding a lightswitch and turning it on, the player receives a "NO CLEAR" message and must later replay that act again. Fortunately, a radar appears in the upper right corner of the screen indicating what direction the nearest lightswitch is in, disappearing as soon as the switch is hit. Also, midway through almost all of the acts, a frustratingly difficult mini-boss that resembles a robotic replica of Dr. Robotnik can be found and fought.
- Marina Madness: A cruise-themed attraction with, curiously, no water (this is because the "boats" you are on this level are actually giant airships). The player must jump from ship to ship to complete this level while dodging flying fish and sailing stingrays.
- Techno Tower: A futuristic-styled tower that the player must climb. In Level 5, the player can hop on a drill machine that burrows through solid walls (but only by pressing a switch that changes where the elevator at the beginning goes, leading you to the tunnel where the drill machine lays in wait.
- Newtrogic High/World Entrance: Between each stage the player visits the World Entrance. Here, one can choose to end/save the game, select a new partner, and choose a new stage.
The bonus stage can be accessed by collecting 20 or more rings and jumping through one of the large rings found hidden throughout a level. In the stage, the character free-falls down a long spiral of rings, power-ups, blocks and exits while the player's rings gradually count down to 0. The stage ends when the ring count reaches 0 or when the character hits an exit. Possible bonuses include a slow-down at the attraction roulette screen or a free pick from the Combi Catcher.
Also, Sonic Advance had a special stage similar in concept to this bonus stage, but the only things that can be found are rings, spike balls, and Chaos Emeralds.
In the special stages, the player moves his character through a hexagonal, fully rendered 3D course to collect a specified set of blue spheres. Rings are collected as seconds and when the count reaches zero or the player falls from the course, the stage ends. When successfully completed, the player is awarded one of six Chaos Rings. Contrary to earlier games in the series, collecting all Chaos Rings does not award the player with special powers (but it does reward them with the best ending, in which Sonic and Tails make cameo appearances).
Special stages can only be accessed through a single large ring at the ending of each level, but the player must have collected at least 50 rings for it to appear. After a player wins all six Chaos Rings, the special stages start over in a wireframe mode.
Upon release, Knuckles' Chaotix gained mixed responses from critics and gamers alike. Some people praised it for its graphics and music and for being one of the better games for the 32X. However, some people showed a dislike of the clunky nature of the "rubberband" physics of the games "buddy system" and the lack of variation between acts of each world.
- Sonic Crackers (also known as "Sonic Studium" and "Sonic the Hedgehog 4") is widely distributed on the Internet, but some controversy exists among fans whether or not Sonic and Tails were originally included in the game. Some have theorized, in accordance with the existence of Sonic Crackers, that they were removed in the early stages of development, while others suspect they might have been included up until late into the game's development, either as immediately playable or as secret characters. A believed alpha version of Knuckles' Chaotix known as
With the recent unearthing of 13 prototype builds of Chaotix, it is now known fact that Sonic and Tails were indeed in the earliest prototypes, as icons for Sonic and Tails were found in the December 7, 1994 build.