From Sonic Retro
Chao Karate is a Chao-based mini-game found in the Chao Cave in the Normal Chao Garden in Sonic Adventure 2: Battle, and the second Chao-based mini game along with Chao Races. In the 2012 re-release, the Battle DLC is required to play this mini game.
In this game, the player can choose to play a Tournament Game or an Inter-league Game. The Tournament Game is the main single-player mode where your Chao fights other Chao in a sequence of 5 Chao in order to claim victory, while the Inter-league Game allows a Chao from the Memory Card in Slot A to battle a Chao from the Memory Card in Slot B.
The player's Chao must defeat the other Chao by comically punching and kicking the other Chao, with the Chao learning stronger attacks as the player levels up their stats, which have different purposes here: Swim becomes the Chao's Defense, which decreases damage taken; Fly is Stealth, which raises the likelihood of dodging attacks; Run is Speed, which is how quickly the Chao attacks; Power is Power, which is how powerful the Chao's attacks are; and Stamina is Health, which is the Chao's overall vitality.
In addition to a health bar, Chao have a Zeal bar that measures its motivation and energy. The Zeal bar gradually decreases over time, but it will increase if the Chao lands a hit on the opponent, and will significantly decrease if the Chao takes damage or misses an attack. If the Zeal bar empties out completely, the Chao loses the will to fight and will start playing around, leaving it vulnerable to attack. The player cannot do much during the fight except watch, but when their Chao loses all its zeal, they need to hit repeatedly to get their Chao back on its feet and fighting again.
To win, the player's Chao must fully deplete their opponent's health bar or knock them out of the ring before the timer runs out or they are knocked out themselves. If the timer reaches zero, the Chao with the most remaining health is declared the winner.
There are multiple difficulty levels: Beginner, Standard, Expert and Super; with the last only being unlocked once a Chao completes the Expert difficulty. Winning each difficulty level awards the player with one Emblem, up to a total of four. The opponents the player's Chao will face on each difficulty are as follows:
|Mode||Chao 1||Chao 2||Chao 3||Chao 4||Chao 5|
|Sonic Adventure 2|