Metroid (species)

Metroid is the eponymous recurring artificial organism in the  series which also appears as an Assist Trophy in Super Smash Flash 2.

Character Description
The Metroid was created long ago by an ancient tribe known as "The Chozo" in order to fend off a threat known as the X Parasite. The Metroids were discovered on Planet SR388 years after their creation. After the Space Pirates discovered the Metroids, they were promptly used as bioweapons, due to the Energy Leeching abilities the creatures possess.

In the original , Samus was sent to Planet Zebes to destroy the Space Pirates, as well as dispose the stolen Metroids. In Metroid II: Return of Samus, the Galactic Federation noted the danger the Metroid posed, and called upon Samus to go to SR388 to eradicate the Metroids once and for all. During the last battle with the Queen Metroid, an infant Metroid hatched and imprinted Samus as its mother. This last Metroid became known as "The Hatchling" and would become one of the most important Metroids in the series.

In Super Smash Flash 2
A Metroid appears as an Assist Trophy in Super Smash Flash 2. When summoned, the Metroid flies around the stage, targeting the nearest opponent. Upon making contact with one, it will latch onto them and start draining their energy, dealing continuous hits of 3% damage each before eventually letting go after attacking thirteen times. Movement is not hampered when a Metroid latches onto an opponent, as they can move about freely. The Metroid can also be attacked, which can cause it to let go of the opponent early. After a certain period of time, or if the Metroid does not latch onto an opponent after six seconds, the Metroid disappears.

Trivia

 * It was initially said that the Metroid in Super Smash Flash 2 was actually the Metroid Hatchling, supported by its small size. However, this was proven to be false when it was enlarged in size to make it more similar to its Super Smash Bros. Brawl version.
 * Metroid, Mother Brain, and Starfy are the only Assist characters that the playable fighters can attack.