Chuchu

ChuChus (or Chuchus) (チュチュ) are jelly-like monsters  that appear in many Zelda games beginning with Majora's Mask,  and are likely relatives of other jelly-like enemies from earlier Zelda titles  such as the Buzz Blob  and Zol. The ChuChu comes in a wide variety of colors and types, including Red, Green, Blue, Yellow, Purple/Dark, Rock and Spiny. As an enemy, they are relatively simple to beat, a simple slash with the sword is all that is required to  take down most varieties.

Characteristics
ChuChus, though they have a standard appearance in every applicable title except  for Majora's  Mask, the general behavior and  physicality remains quite constant despite differences in appearance. In Majora's  Mask, Chuchus appear as bottom-heavy blobs of  jelly in different colors, with a large mouth and eyes on stalks. Uniquely, the Chuchus in Majora's Mask are entirely transparent and very pale in color (for example the Red Chuchu is actually more of a pale  pink). Dependent on color, they contain various items within their bodies, such as a Recovery Heart,  Magic Jar  or Arrows. Unlike Majora's Mask, the Chuchus of later  titles resemble that of The Wind Waker  design -  they are small, top-heavy  globs that use their "feet" to slide around the landscape. As the later titles progressed, different types of Chuchus emerged with simplistic,  yet highly varied personalities including the incorporation of  electricity, rock-like  helmets, and ice powers into their battle strategies. Nevertheless, the ChuChus kept to their Majora's  Mask roots for the most part,  as even into Spirit  Tracks they used color to  denote behavior, power capability, and in-game frequency. Of the Chuchus in the Zelda universe, the red variety is the most common, however, the green,  yellow, and purple versions have seen quite the incorporation as the  series progressed through the years.

Twilight Princess is the only title to provide blobby, slug-like  ChuChus, called simply Chus. While they behave similarly to  other ChuChus in that they denote characteristics and type by color,  move slowly, and tend to jump on Link when threatened, these Chus also  have the ability to split and merge. A large Chu will split into two smaller Chus, when attacked, and will keep splitting until they are too  small to do so. When two Chus of different colors collide, they will merge and grow, retaining the color of more common Chu (from most to  least: Purple, Yellow, Red, Blue, Rare).

In few titles, such as The Wind  Waker and Twilight Princess, Chus tend to leave behind Chu Jelly, a vital ingredient used to  synthesize potions at the local Potion Shop. A certain number of Chu Jelly ingredients are required to help the potion chemist at the Potion Shop  make a specific potion; the color of the Chuchu denotes the type of  potion its Chu Jelly can be made into, for example, a Green Chu will  yield Green Chu Jelly good for making a Magic Potion (as it is also  green), once the required quantity of such Chu Jelly is acquired.

Red
The Red ChuChu is the most common of all versions, and thus is the face of the ChuChu in terms of standard behavior and  appearance. Their greatest example is seen in The Wind Waker; they are the lowest form of ChuChu and the easiest to slay. Their attack deals little damage, and can be tricky in groups (though rarely  forming any more then three at a time). in Majora's Mask, the Red  Chuchu releases a Recovery Heart  when killed, but in later titles such as Twilight Princess,  the creature yields Red Chu Jelly, which in turn can be drunk on the  spot to refill eight hearts and boost attack power or can be used to  synthesize a Red Potion  in The Wind  Waker, one that specializes in  life replenishment, at a Potion Shop.

Green
The Green ChuChu appears legitimately in only two titles, and has a drastically  different appearance and behavior in each appearance. In Majora's Mask, the 'Green Chuchu contains a Magic Jar which will be dropped once defeated, otherwise it behaves like and is often apparent in the same  area as it's relative, the Red ChuChu. In Phantom Hourglass, Green ChuChus  only appear in the Temple of  Courage. They have the ability to shrink into a puddle to evade Link's attacks. Other than that, though, they can still be easily defeated with a swipe of the  sword.

Interestingly, Green Chus are extremely rare in Twilight Princess, and the Chu Jelly they provide has no effect on Link whatsoever, leading theorists to believe this Chu was  created for the sole purpose of replenishing Link's magic meter, seen  only in the beta version. Since the magic meter in Twilight Princess was removed, perhaps the usability of this Chu's jelly was removed as well.

Blue
Blue ChuChus, pale-blue  in color, are one of the rarest types, found in small, always  significant quantities in the titles they appear in. In Majora's Mask, the Blue Chuchu holds no items, and is described by Tatl  as "basically just a blob of water". Only a single example of this color ChuChu appears in the game, found in Great Bay  Temple where it must  be frozen using an Ice Arrow  in order for Link  to reach a particular area. Blue Chuchus are also the only type of ChuChu that can be frozen in Majora's Mask.

The Blue ChuChu in The  Wind Waker, The Minish Cap, and Phantom Hourglass  is highly electrified. It also drops the rarest type of Chu Jelly, Blue Chu Jelly. The Blue Chu Jelly fully replenishes both Magic Power and Recovery  Hearts, once made into  a Blue Potion  by Doc Bandam,  or when drunken immediately from the bottle after defeating it in Twilight Princess. To emphasize their scarcity, there are only twenty-three  Blue ChuChus on various islands in The Wind Waker,  only dropping their rare Chu Jelly once.

Yellow
The Yellow ChuChu is unique in that it is electrified in all of its incarnations save for  its appearance in Majora's  Mask. In Majora's Mask, the Yellow Chuchu holds an item, usually Arrows,  and appears in only a few locations (usually within dungeons). Yellow Chus are even rarer in The  Wind Waker than the already-uncommon Blue  ChuChus. These foes can only be struck with the sword in close combat when their protective energy field is inactive. Link must either wait for their electricity to fade or stun them with an item such as the boomerang or the Whirlwind in order to inflict damage.

Interestingly, it does not drop an individual Chu Jelly in The Wind Waker,  instead rewarding Link with Green Chu Jelly upon defeat. When destroyed, and the Chu Jelly received from this foe in Twilight Princess can be used in the same vein as Lantern Oil.

Purple
In The Wind Waker, Purple  ChuChus are only harder to find  than Blue ChuChus because they tend to live in areas away from direct  sunlight, within the ancient temples. Purple ChuChus are considered the most impregnable, as almost any attack against them is useless. When a Purple ChuChu is attacked with the sword, bow or even the Skull Hammer, they will break apart and  reform; the only known way to beat Purple ChuChus is to force them into  direct sunlight, which will turn them to a fragile, yet breakable stone. Or like most other enemies, Link can shoot it with a Light Arrow.

The Purple ChuChus of Spirit  Tracks give off an an electric  aura, but unlike Yellow ChuChus, they cannot be stunned. The only way to defeat them is to strike them with a sharp object with the Whip, such as the helmet of a Helmet  Chuchu (with a metal, spiky helmet this time). A Phantom's blade, arrows or bombs can also defeat these. When the Chu Jelly of the Purple Chu is drunken in Twilight Princess, it will yield a random effect similar to the Nasty Soup,  sometimes positive (i.e. replenishing 8 hearts) or negative (i.e.  taking away hearts).

Big
A Big Green Chuchu is the boss for the first dungeon (Deepwood Shrine),  in The  Minish Cap. It is really just a normal Chuchu, but seems enormous because Link is Minish-sized at the  time. A Big Blue Chuchu is a miniboss in the Temple of Droplets, which is Minish-only as well. Unlike Big Green Chuchu, Big Blue Chuchu  can electrocute you.

Helmet, Rock, and Spiny
These three ChuChu varieties  are very  similar as they all involve the encasement of the head of the  ChuChu  with a hard surface, whether it be rock or spikes. Helmet ChuChus, as they are called in Spirit Tracks, pay tribute to their eponymous name  with the spiky  helmet covering their entire heads. The helmet must be  pulled off using  the Whip, at which point the helmet can either be   thrown back at the  ChuChu to defeat it or thrown away to finish it off   with the sword. The Rock   ChuChu reverts to a Red  ChuChu  after its hard helmet is destroyed with a sharp blow to the  head, in The  Minish Cap, or destroyed with a Bomb, pulled off with the Grappling Hook   or smashed with the Hammer   in Phantom   Hourglass. In the latter game,  this ChuChu variety likes to hide out beneath large rocks, busting out   whenever Link draws near. The Spiny Chuchu  has an excellent defense mechanism, puffing out spikes all over its   body when approached, in The Minish Cap. To defeat them, Link must wait for them to retract their spikes, or use  a bomb to destroy the creature immediately.

Ice
The white Ice  ChuChus of the Snow Realm in Spirit Tracks  need to be stunned using the Whirlwind or the Boomerang before attacking. Otherwise, they freeze Link, requiring the player to rub the screen with the stylus to de-thaw the young hero.

Rare
In Twilight  Princess, Rare Chus are pearl-colored and  sparkle. Rare Chus can be found in any area Chus are normally found, however the chances of  finding them are incredibly slim. The Cave of Ordeals and two secret grottos;  under a tree at Snowpeak  and in the Gerudo Desert  are the only certain places to find them. Outside the cave, the small ledge on Death Mountain,  under the large tree atop Lake Hylia between midnight and dawn, and  also near Snowpeak  are places reported to have had Rare Chus. A Rare Chu can also be found within a secret grotto  beneath Ordon Ranch  accessed via a dig spot within the barn.

Rare Chu Jelly acts the same as Great Fairy's Tears. However, scooping up Rare Chu Jelly is difficult, as not only are they hard to find, but the Rare Chu  is the first to be targeted by Purple Chus to merge. If a Rare Chu and any other Chu merge, the Chu will become the other color, canceling out  the Rare Chu. Additionally, if you get Rare Chu Jelly, any Rare Chus set to appear will be replaced with Yellow Chus.

Trivia

 * If a Blue Chu and Yellow Chu merge, they will create a Green Chu, in the Wii version of Twilight Princess.   There are few cases of these two types being in the same area, so it is  very hard to create a Green Chu. The best place may be the Cave of Ordeals  on Floor 12. To perform Link must have some Rare Chu Jelly so that the  Rare Chu in the room is replaced with a Yellow Chu. The young hero must  tread around carefully to avoid any Purple Chus or Red Chus fusing with  the Blue or Yellow Chu. The resulting jelly from a Green Chu does  nothing, and is likely a remnant from an earlier version of the game  that featured a magic meter. Attempting to fuse a Yellow and Blue Chu in  the GameCube version will result in a Purple Chu, but Green Chu Jelly  can still be obtained using a cheating device. Additionally, one can  obtain Black Chu Jelly with a cheating device, which has the same effect  as Nasty Soup  (random effect).