Rotom (Japanese: ロトムRotomu) is an Electric/Ghost-type Pokémon. Rotom can transform into various forms which resembles household appliances.
Rotom is a small, round, ghostly creature with a plasma-based body. Its vibrant, orange body mass is spherical with a long, spike-shaped, antenna-like feature atop its head, and a small, round orb on its underside. It is enveloped in a glowing aura of cyan-bluish plasma, with lightning bolt-shaped appendages on either side of its lower body. Rotom has two ovular, blue eyes and a small, grinning mouth on its face.
Rotom is very clever and mischievous. It enjoys teasing and frightening people and Pokémon. It often invades appliances and takes control of machines, allowing it to change its form.
Rotom is able to infiltrate electronic devices, namely appliances, and take control of machines, allowing it to change form, as well as its Ghost type. It can enter a lawn mower to assume its Mow Form, a toaster oven to assume its Heat Form, a refrigerator to assume its Frost Form, a washing machine to assume its Wash Form, and a fan to assume its Fan Form.
As of Generation VII, Rotom can enter a PokéDex and transform itself into such a shape. This allows it to communicate with people and Pokémon alike.
Fan Rotom is the only form with a special move whose base power isn't over 100.
Before the Generation V games, many of Rotom's Formes were the only Pokémon that could learn their special attacks, but weren't that attack's type.
As of the official Japanese tournament held in 2008, all of Rotom forms have been banned from official tournaments. This is due to the special status of the alternate forms as event-exclusive Pokémon.
From Pokémon Black and White on, when it changes to Fan Rotom, it becomes a Flying type, which is immune to Ground type attacks, and yet it still has the ability Levitate, making the ability useless.
Rotom is the only Electric-type Pokémon with multiple forms.
It may be based on a Poltergeist or related to the phrase "ghost in the machine". As Banette originated from a castaway doll, Rotom may have originated from a toy robot. It may also come from a species of Obake, which are objects that become animate when reaching their 100th year of existence, and a Bakemono, which is referring to a state of transformation or shape-shifting.
Rotom may also be based on ball lightning and its mysterious and seemingly mischievous behavior. Ball lightning was once described as a living mythological "species of fire" known as ignis fatuus, which loosely translates to "foolish/mischievous fire".
Pokémon Platinum reveals Charon named Rotom. Rotom's name is actually the word "motor", spelled backwards, due to the fact that all of the household appliances it can turn into have motors. It is one of the few Pokémon that is an actual word spelled backwards. It may also come from rotor and phantom.