Rayquaza

Rayquaza (Japanese: レックウザ Rekkuuza) is a /-type Legendary Pokémon, as well as the version mascot for Pokémon Emerald. It is said to dwell in the ozone layer of the atmosphere.

Physiology
Rayquaza is a long serpentine Pokémon with greenish body.It has pink lining on the mouth.

Behaviour
Rayquaza seems to be a very angry Pokémon when it tried to kill a Deoxys.

In the Hoenn region's mythology, it was said that Rayquaza stopped the fighting between Groudon and Kyogre. It lives in the ozone layer far above the clouds and cannot be seen from the ground. It is noted for protecting its territory fiercely.

Evolution
Rayquaza does not evolve.

Games
Rayquaza is a Generation III Pokémon, first appearing in the Pokémon Ruby and Sapphire games. In 2005, Rayquaza became the version mascot for the Pokémon Emerald game. In all three games, Rayquaza can only be obtained at the Sky Pillar. It can be caught after the eighth Gym,(Only for Pokémon Emerald) making for an easy Elite Four.

In Red Rescue Team and Blue Rescue Team, Rayquaza plays a key role in the story. Xatu warns all of the Pokémon in Pokémon Square that a large star is falling and is going to destroy the planet, and says that the only way to get rid of it is to ask Rayquaza to destroy it. The main character must use Xatu's teleporting stone to reach the Sky Tower, where Rayquaza dwells. When the main character meets Rayquaza, it is extremely enraged to see that Pokémon from the ground have come "where they are not supposed to be". When the player beats Rayquaza, it will realize its mistake. The star that will destroy the planet is coming near, so Rayquaza blasts it with its Hyper Beam. The blast is so overwhelming that the main character and his partner fall off of Sky Tower.

It can also be found in HeartGold and SoulSilver in Embedded Tower after the player obtains Kyogre (HeartGold) and Groudon (SoulSilver).

Super Smash Bros. Brawl
Rayquaza is the second main boss the player must fight in Super Smash Bros. Brawl's Adventure Mode, The Subspace Emissary. Diddy Kong runs to find help for Donkey Kong, and comes across a large lake. He notices a destroyed Arwing nearby, and goes to investigate. Rayquaza appears out of the lake, angry that Diddy trespassed into its territory. It grabs Diddy, but Fox emerges from the Arwing and uses Fox Illusion to free Diddy Kong from Rayquaza's grasp. The two quickly team up and defeat Rayquaza. Rayquaza's appearance is also notable because it is the only boss in The Subspace Emissary who is fought by a group that does not include any other characters from its own series.

It is interesting to note that Rayquaza was found within the lake as opposed to its usual dwelling, the sky.

Rayquaza appears later in the Great Maze, as one of the eight bosses the player must face before completing the adventure.

Rayquaza also appears in Brawl's stadium, in a mode called Boss Battles. Rayquaza is one of the ten bosses that the player must fight.

Anime
Rayquaza makes its debut in the 7th movie Destiny Deoxys. Like all other Legendary Pokémon, Rayquaza is a truly powerful Pokémon. Four years before the main movie, Rayquaza had fought against Deoxys because it thought the Pokémon was invading its territory when the meteorite Deoxys used for travel landed on the earth.

When Iris was leaving Blackthorn City with Axew and her newly captured Gible, she spotted Rayquaza flying through the clouds in the sky.

Trivia

 * Rayquaza is one of few Pokémon resembling dragons from oriental lore along with Gyarados.
 * Rayquaza is one of the only Pokémon bosses to be in Super Smash Bros. Brawl.
 * Rayquaza is based on Ziz of Judeo-Christian religion.
 * Rayquaza is one of only two Pokémon that can naturally learn the move Fly, the other being Salamence.

Etymology
Its name may be derived from ray and Quasa, describing how Rayquaza lives under the influence of solar phenomenon as the sun's rays. The derivation of the word quasar may be a misunderstanding of what really is a quasar, or an indication of a cosmic origin. Perhaps the Quaza is a reference to Quetzalcoatl as Quetzalcoatl is represented as "feathered serpent". This legend has made ​​the heavens and the food for humans, and the heavens gave Rayquaza. We also see that Rayquaza could be the legendary creature known as Ziz or Renanim. It could also be based on the mythical dragon of Chinese and Japanese culture, (神龙) Shenlong. According to oriental mythology, Shenlong dwells in heaven and controls the climate, just as Rayquaza does.