Sonic Battle

Sonic Battle is a fighting game for the Game Boy Advance. The gameplay consists of 2D sprites fighting in 3 dimensional environments similar to the Double Dragon games. The special move configuration is very similar to Super Smash Bros. in that you can pick it up and play, and that there are no complicated combos you need to memorize to perform special moves.

Playable
Sonic is treated as an excellent character for any use, as he is the second fastest and fairly strong with good range on multiple attacks. Tails is treated as slightly weak, but makes up for it with rather decent attack power. Rouge is treated as very technical and a bit more advanced, as her attacks and movements are slightly different than others. Amy is given decent speed and high power, making her effective for multiple situations Knuckle's is close range and hard to hit with from distance, however he is very strong and increases his power extremely fast Cream is shown to be slow and weak, with powerful heal abilities Shadow is treated as the fastest character in the game, however most of his attacks have long recovery time. Emerl is customizable and therefore is determined by the user, however alone using his basic skills, he is the slowest and weakest character which is contrasted by his ultimate skills making his the fastest and strongest.
 * Sonic the Hedgehog
 * Miles "Tails" Prower
 * Rouge the Bat
 * Amy Rose
 * Knuckles the Echidna
 * Cream the Rabbit
 * Shadow the Hedgehog
 * Emerl

Unlockable

 * E-102 Gamma (No episode)
 * Chaos (No episode)
 * E-121 Phi (Only in multiplayer mode when two people choose the same character)

Non-Playable

 * Dr. Eggman (Second to Final Boss)
 * Ultimate Emerl (Final Boss)

Arenas/Unlockable
All arenas except for Death Egg can be used in Multiplayer.
 * Emerald Beach (Sonic, Tails and Emerl's story)
 * Tails' Lab (Tails, enter to virtual training in Emerl's story)
 * Chao Ruins (Knuckles)
 * Battle Highway (Shadow)
 * Club Rouge (Rouge)
 * Amy's Room (Amy)
 * Library (Cream)
 * Metal Depot (Chaos Gamma)
 * Holy Summit (Chaos)
 * Death Egg (Has to be unlocked by completing story mode)
 * Colosseum (Used during virtual training, only available during Emerl's story)
 * Green Hill (Has to be unlocked by completing story mode)

Story
About 4000 years ago, a sentient weapon was created by an ancient civilization. After being lost for millennia, the weapon, called a Gizoid, was unearthed and researched by Prof. Gerald Robotnik. It remained dormant for another half century before being discovered by, of all people, resident would-be ruler of the world and Gerald's grandson, Dr. Eggman. Frustrated at his inability to get the dormant Gizoid to work properly, Eggman dumped the contraption at Emerald Beach... where it was discovered once again, this time by planet's resident hero, Sonic the Hedgehog.

The Gizoid, which Sonic dubs Emerl, gets wrapped up in the affairs of Sonic's friends, allies and rivals. Through his encounters with Sonic, Tails, Knuckles, Amy, Cream, Gamma, Rouge, and Shadow, Emerl grows and evolves from a soulless robot into a fun-loving mech with personality traits from all of the above. But while the gang is having fun raising their new mechanical toy, there are those who recognize Emerl's true power. Now that the Gizoid is working again, Eggman's got his eye on it, Rouge wants to turn it into a master thief, and Shadow senses that, despite their efforts to humanize him, Emerl is still designed and programmed to be a weapon of mass destruction.

Trivia

 * Some fans think that Sonic Battle ' s story takes place after Shadow the Hedehog and before Shadow joined G.U.N., for in Shadow the Hedgehog, Shadow doesn't know of the ARK or Maria Robotnik, but in Sonic Battle he does.
 * Oddly, the seven Chaos Emeralds are all green in this game, and the Master Emerald does not have its own separate sprite, while the shattered emerald has it's own sprite for the shards.
 * Strangely, when Sonic gets the Master Emerald, he states "A Master Emerald" but this might be a typo.
 * The story is later continued in Sonic Advance 3 (in which a new robot, Gemerl, is built from Emerl's data), and heavily referenced in Sonic Chronicles: The Dark Brotherhood.
 * Some fans consider the game's story to be not canon to the rest of the series (and by a far stretch, Sonic Advance 3 and Sonic Chronicles: The Dark Brotherhood), due to it's contradictive nature in some respects, be it the false coloration of the Emeralds or the changes to Gerald's reports in respect to the time they were written in.