Magikarp

Magikarp (Japanese: コイキング Koikingu) is a -type Pokémon introduced in Generation I.

Physiology
Magikarp is a Fish Pokémon. Its body is made up of/covered in red scales. Its fins are either yellow or white. They also have "whiskers" or Maxilliary Barbells. Female Magikarp have white barbells while male Magikarp have yellow barbells. Magikarp refers to them as his magnificent barbs in PokéPark Wii: Pikachu's Adventure.

Gender differences
The way to tell a male and female Margikarp apart is that an male Magikarp has gold whiskers while an female has white whiskers. In Pokemon GO and its Water Event, the whiskers of the female Magikarp appears to be white silver or platinum. This also applies when it evolves into a female Gyarados as its whiskers remain white silver than its original blue.

Natural abilities
Magikarp have the ability Swift Swim, which increases a Magikarp's Speed when it is raining. Despite being strong in the past, its present-day descendants are considerably weaker. It struggles to swim against even the weakest of currents.

Evolution
Magikarp evolves into Gyarados at level 20.

Game info
Magikarp is the most common Pokémon in the waters of all the Pokémon regions. It can be found in every body of water in Kanto, Johto, Hoenn, and Sinnoh. It is considered to be the weakest Pokémon because it can only use three moves. It is a hardy Pokémon that can thrive in any body of water, no matter if the water is freshwater or saltwater. It can even thrive in polluted waters. However, if it is taken care of properly, it evolves into a magnificent Gyarados, at level 20. Until it reaches level 20, it is utterly useless.

Anime
Magikarp first appeared in the anime in Episode 001 - "I Choose You, Pokemon!" When Ash and Pikachu are fleeing from a flock of Spearow, they jump into a lake to escape, and a Magikarp is seen swimming away followed by a Gyarados, which chases Ash and Pikachu out of the lake.

Magikarp's first major appearance was with Team Rocket in Episode 015 - "Battle Aboard the St. Anne". James gets a Magikarp from a dealer, who cheated his money or bottle caps three times in the whole series of Pokémon Anime, in a golden Poké Ball, of which the gold color disguised the red part of the Poké Ball. It then evolves into a Gyarados, when James kicks it away after the ship sank. The newly evolved Gyarados then uses Dragon Rage to send Ash, Misty, Brock, Pikachu, and Team Rocket blasting away to an island.

Trivia

 * Magikarp is generally regarded as the weakest Pokémon in the Pokémon games. Stat-wise, however, Wishiwashi (in its Solo Form) is.
 * Cosmog can actually be considered weaker than Magikarp, as Cosmog can't learn any damage dealing moves.
 * In Pokémon Platinum Version, Magikarp is both the lowest- and highest-level non-glitch Pokémon available for capture. By using the Super Rod at a pond in the Resort Area, this Pokémon can be encountered and caught at levels ranging from 1 to 100.
 * Pokémon Mystery Dungeon: Explorers of Time & Explorers of Darkness are the only games in which Magikarp can learn moves via TMs. This holds true in Pokémon Mystery Dungeon: Explorers of Sky.
 * According to Misty in Pokémon Shipwreck, Magikarp are just scales and bones, making them unsuitable for eating.
 * It is similar to Feebas in that it is a weak fish Pokémon that evolves into a powerful serpentine one.
 * In Gen VI onwards its in-game sprite just helplessly flops around. Curiously, other fish Pokémon, such as Goldeen, do not exhibit such animations and seem to "swim" in the air. This is probably to signify it's weakness.

Origin
Magikarp is based on a carp. Its evolution into Gyarados is based on a Chinese myth about how carp that leapt over large and tall waterfalls would transform into dragons.

Etymology
Magikarp is a combination of magic and carp. The "magic" part may be said ironically, as it seems to convey something wondrous about a mundane and useless Pokemon.