Story: While exploring, Sonic finds a beat-up robot on the coast of Emerald Beach. Sonic decides to take the robot to Tails. Shadow soon appears and asks for the robot. Sonic doesn't want to give up the robot, which sets the mood for a fight.

Modes: There are four different modes of game play: story, battle, challenge, and training. In addition to these modes are mini games and the ability to view your battle record and change options.

Story Mode follows the adventures of the characters as each one discovers something about Emerl. The first episode (or story) follows Sonic after he finds a robot. After finding out that the robot runs on Chaos Emeralds, Sonic names the robot Emerl. Emerl can capture fighting moves during battle and then use these skills. These skills are set by pressing the R button. There are over 300 skills or extras (such as body color) that Emerl can learn. After fighting a battle, Emerl earns skill points. These points vary depending on how well you perform the battle. You get the most points by not getting hit during the battle, fewer points for never dying, and one point for finishing the battle. The more points Emerl earns, the more skills he will be able to use.

In Battle Mode you can play against other people or the computer. You can set your own rules, such as the first person to get 5 KOs wins. In addition, you can select from a variety of battle locations in which to fight.

For Challenge Mode you select a character and then fight for 5 rounds. In order to move on to the next round, you must have 10 KOs. At the end of each round your statistics for that round are displayed. These statistics include how long you played the battle, how many times you died, and your score for each category.

Training Mode lets you practice your skills. You can have your opponent perform certain skills, attacks, or just stand there in order to practice your own skills.

There are quite a few mini games that are multiplayer. The only mini game that is not multiplayer is Knuckles' Mine Hunt. If you've ever played Minesweeper, you already know how the game works: punch all the squares that don't have mines. The A button makes Knuckles dig into the ground, which reveals a number (or a mine if you're unlucky). If you think you found a mine, use the B button to drop a marker that looks like a Chao. The more rounds you complete, the more mines there are. Once Knuckles hits a mine the game is over.

Chaos Emeralds: Chaos Emeralds are obtained during the game's story after beating different battles. Each Chaos Emerald gives Emerl more power. (Note: Sonic gave the robot the name Emerl since he runs on Chaos Emeralds.)

Miscellaneous: Most of the time playing the game will be spent on Story Mode. Emerl has many skills to acquire, which means you must fight in a lot of battles if you want to collect them all. Repeating Story Mode does have its advantages. For instance, after beating the game, you can replay a character's episode and at the end read a selection from Professor Gerald's journal. Professor Gerald (Eggman's grandfather) was the one who originally discovered Emerl. (Going into more detail will spoil the story.)

Sonic Battle is definitely a unique fighting game. Just like most Sonic games, the controls are simple. The ability to heal and charge the Ichikoro Gauge (which gives you the power to KO a character in one hit) can come in handy when you have trouble defeating an enemy.