Castform

Castform (ポワルン Powarun in Japanese, Formeo in German and Morpheo in French) is a fictional character of the Pokémon franchise.

Its name is a combination of forecast and transform, being its body changes with the weather.

Appearance
Castform's appearance is unique in that it is mutable - although not the shapeshifter that Ditto is, Castform nevertheless has four different forms it can change into. Its "normal"/official form, displayed in the Pokédex, is that of a large floating grayish head with a rudimentary lower body, white markings around its eyes and a hook-like protrusion on the top of its head. See below for information on Castform's other forms.

Biology
Castform is one of few human-made "artificial" Pokémon. It was created on purpose by the researchers of the fictional Weather Institute in Hoenn region as an experiment in weather forecast and manipulation.

Castform's cellular structure is closely related to the weather conditions, meaning that Castform can both affect and be affected by the weather. Depending on the current weather and climate, Castform's emotions and even body are altered. In this way, Castform tries to adapt itself to multiple environments.

This extraordinary trait is referenced in the video games through the Forecast ability, which changes Castform's type and appearance depending on the weather. In weather not particularly extreme, Castform's type is normal and its appearance is as described above.


 * In intense sunlight (induced by the Sunny Day move or Groudon's Drought ability) Castform becomes a Fire type. Its head turns red, its eye markings become yellow and its head is enclosed in a translucent orange orb adorned with smaller orange orbs, giving the impression of a stylized sun. Its lower body becomes larger and paler, like a puffy white cloud.


 * In torrential rain (caused by the Rain Dance move or Kyogre's Drizzle ability) Castform becomes a Water type. Its head turns dark blue, its eye markings become a lighter blue and its head is enclosed in a blue raindrop shaped structure. Its lower body grows and darkens, reminiscent of a storm cloud.


 * In hail fall (brought about by the Hail move) Castform changes into an Ice type. Its head turns violet, its eye markings become a lighter violet and its head is enclosed in a complex emerald-colored structure that is meant to represent a snow cloud.


 * In a Sandstorm, Castform doesn't change, but its Weather Ball attack becomes rock-type.

Visit this page for sprites of all four Castform "modes".

In the video games
Castform is only available in Pokémon Ruby, Sapphire and Emerald. Only one Castform exists in each game, and it is awarded to the player after he or she successfully defends the Weather Institute against Team Aqua or Team Magma, depending on game version.

Castform's man-made nature is reflected in its uniform stats, all of which have the average value of 70. Its natural moveset is entirely geared towards manipulating the weather conditions. Castform's knowledge of the weather changing techniques Sunny Day, Hail and Rain Dance, together with the Weather Ball attack and the Forecast ability (both traits unique to Castform) encourage a very particular strategy in battle:

The Weather Ball attack has a mediocre base power of 50, but it becomes much more powerful under a weather condition, receiving the following bonuses:


 * Weather Ball's power doubles under a weather condition (Sunny Day, Rain Dance or Hail but not Sandstorm).
 * Weather Ball's elemental type changes to Fire for Sunny Day, Water for Rain Dance and Ice for Hail. Since Castform's type changes accordingly, this results in a 50% same-type attack bonus. (Weather Ball will become Rock type if Sandstorm is used, and in Pokémon XD, Shadow type if Shadow Sky is used, but Castform's type will not change.)
 * Sunny Day and Rain Dance increase the power of Fire and Water-type attacks respectively by 50%.

This results in a power as high as 225 (for Fire and Water) or 150 (for Ice). So, the most obvious strategy is to use the weather changing move whose type has an advantage against the opponent and then use Weather Ball.

In the animé
Castform was featured in episode #349 (Unfair weather friends), in which operatives of both Team Aqua and Team Magma attacked the Weather Institute trying to steal data on Kyogre or Groudon, as well as weather-changing technology.

In the card game
Though Castform has made eight Basic-class appearances in card format, it is only considered to have made two official appearances, for each set has four prints of the Pokemon, representing each of Castform's four forms.
 * EX Hidden Legends (As Castform, Colorless)
 * EX Hidden Legends (As Rain Castform, Water)
 * EX Hidden Legends (As Snow-Cloud Castform, Water)
 * EX Hidden Legends (As Sunny Castform, Fire)
 * EX Delta Species (As Castform, Colorless)
 * EX Delta Species (As Rain Castform, Water)
 * EX Delta Species (As Snow-Cloud Castform, Water)
 * EX Delta Species (As Sunny Castform, Fire)

Any Castform can be switched out for any other Castform card on the field with its Poke-Power, Temperamental Weather.