Debuting in The Legend of Zelda: Majora's Mask, they are often the one of the more common type of ChuChu in the games they appear. Usually serving as a slightly harder variant of the most common ChuChus of their respective games.
The Legend of Zelda: Majora's Mask
In The Legend of Zelda: Majora's Mask, the Green ChuChu is the most common type of ChuChu in the game alongside the Red ChuChu. They are very common to find in the Termina Fields. Most ChuChu, beside Blue ChuChus, carry different items in their bodies in Majora's Mask. Green ChuChus are known to carry Magic Jars, which are visible through their translucent bodies.
"That's a Green Chuchu. It's nothing to be afraid of...It usually has something in its stomach that's of use."
The Legend of Zelda: The Wind Waker
In The Legend of Zelda: The Wind Waker, Green ChuChus are slightly stronger versions of the Red ChuChus. Their main difference is that they can shrink into a puddle to avoid attacks. They are found in a lot of places like Pawprint Island, Dragon Roost Island, the Forbidden Woods, the Earth Temple and Wind Temple. They can drop green Chu Jelly, which can be used to create Green Potions.
Wind Waker Figurine
"There are ChuChus of many different colors, all with their own distinct characteristics. In general, they are most susceptible to projectile weapons."
The Legend of Zelda: The Minish Cap
Green ChuChus are very basic in The Legend of Zelda: The Minish Cap where they are very common. Unlike their red cousin, they are often fought alone instead of in groups.
The Minish Cap Figurine
"Appear in various areas. Chuchus come in many colors. Each color is a little different, but ranged weapons work well against all."
The Legend of Zelda: Twilight Princess
Green ChuChu are quite are very different than its past incarnations in The Legend of Zelda: Twilight Princess. In this game, ChuChus can fuse together to become bigger ChuChus and be split into smaller ChuChus if hit by a sword while being bigger than the regular size. It drops Green chu Jelly, which has no effect. This comes from the fact that Green ChuChus are more of an easter egg left into the game by the developers from the time where magic was supposed to be used in the game. Green ChuChus can only be seen by having Yellow ChuChus and Blue ChuChus fuse. This is impossible on the Nintendo GameCube version.
The Legend of Zelda: Phantom Hourglass
The Legend of Zelda: Skyward Sword
The Green ChuChu is the most basic type of ChuChu in The Legend of Zelda: Skyward Sword. Like in Twilight Princess, they can fuse and be splitted but splitting them horizontally will only make the top half fall on the lower one making both fuse back again. Unlike all other ChuChus, they have no elemental ties at all.
"These creatures prefer exceptionally damp environments. They will encompass and digest anything they can absorb into their gelatinous bodies.
As they have no genders, they are believed to increase their population by dividing themselves into several smaller-sized Chuchus."
Hyrule Warrior series
Green ChuChu are featured as a rare enemy in the Hyrule Warriors series. They are only featured in Hyrule Warriors Legends and Hyrule Warriors: Definitive Edition where they can only be defeated by the Hammer and will drop a magic Jar upon defeat.
The green ChuChus are featured as one of the common enemies in Battle Quest, the Zelda themed mini game of Nintendo Land. Like in The Wind Waker they are the slightly stronger variant of the Red ChuChu with the ability to shrink to avoid attacks.