While it is not known to evolve into or from any other Pokémon, Rotom has the ability to possess the motors of certain appliances and change forms. It also learns a new move depending on which appliance it possesses. Rotom's form can be changed in by allowing it to possess the appliances in Rotom's Room or from the Rotom Catalog.
When it has not possessed any appliance or is possessing a light bulb, it is dual-type Electric/Ghost, and learns Thunder Shock if the move it had in its other forms is the only move it knows.
Rotom is a small, orange Pokémon that has a body of plasma. It is mostly spherical, with a bulb below its body and a long pointed protrusion on top, making it shaped like a lightning rod. There is a whitish blue aura of electricity around it that forms lightning bolt-shaped appendages. It has teeth, and its unique, blue eyes have a dividing line across them. In its base form, Rotom cannot be touched by anyone without the latter being shocked in the process. According to the Rotom Catalog, Rotom in its base form is possessing a light bulb.
Rotom has the ability to enter and control appliances. Rotom typically use their abilities to make mischief, often using the household items they possess to pull pranks on unsuspecting people, as seen in the anime. Despite this, some Rotom have taken to inhabiting electronics with the intent of helping others. The Rotom Pokédex, Rotom Phones, Rotomi, Rotom Bike, and Drone Rotom are some examples. The creation of Rotom Pokédex in particular was inspired by Mow Rotom. Some of these particular forms allow Rotom to speak human languages. These forms show that Rotom is also highly intelligent. As also shown in the anime, Rotom has the ability to time travel. Rotom tends to reside in abandoned buildings. Research continues on Rotom and its ability to power unique motors.
Rotom has five alternate forms: Heat Rotom, Wash Rotom, Frost Rotom, Fan Rotom, and Mow Rotom.
Rotom's forms can be accessed by possessing specific household appliances with a special motor, namely: a convection microwave oven (Heat Rotom), a washing machine (Wash Rotom), a refrigerator (Frost Rotom), an electric fan (Fan Rotom), and a lawnmower (Mow Rotom). When Rotom changes forms, its eyes and electric aura change colors, and its aura appendages take on different shapes: red with oven mitts as Heat Rotom, blue with clothespins as Wash Rotom, purple with lightning bolts as Frost Rotom, yellow with air curls as Fan Rotom, and green with a ripped strip as Mow Rotom.
In modern Sinnoh, Rotom's forms were said to have been first discovered and documented by Charon. However, Rotom existed in Hisui and was also documented in the Hisui Pokédex. The electric fan that Rotom inhabits to become Fan Rotom was invented by a boy, and was the first Rotom-related appliance to be developed, leading to the creation of many other appliances like it. The washing machine model that Rotom can inhabit has been discontinued, which causes its price to skyrocket. Heat Rotom will become lethargic if the oven it possesses is malfunctioning.
In The Dex Can't Help It!, a Wash Rotom was involved in an accident caused by Ash's Pikachu that ejected it from the washing machine and caused it to get swapped with the Rotom Pokédex. Eventually, the Rotom were swapped back to their original places.
Rotom first appeared in Robust Rotom, where it caused havoc for Diamond and Pearl at the Old Chateau until Diamond understood that it only wanted to return in its plasma television and led it there.
During the subsequent fight against Charon and Giratina, Rotom initially joined the battle transforming into its five forms, then left the fighting to the other legendary Pokémon only to strike at the very last, destroying Charon's device that allowed him to control every Pokémon and thus putting an end to his evil plans. After that, Rotom decided to stay with Diamond.
Moves marked with an asterisk (*) must be chain bred onto Rotom
Moves marked with a double dagger (‡) can only be bred from a Pokémon who learned the move in an earlier generation.
Bold indicates a move that gets STAB when used by Rotom
Italic indicates a move that gets STAB only when used by an evolution of Rotom
Click on the generation numbers at the top to see Egg moves from other generations
When Rotom changes into an appliance form, it learns a new move in the same way that other Pokémon may learn new moves upon evolving; if Rotom would change from one appliance form to another and knows the special move of its current form, the old special move is automatically forgotten and Rotom learns the new one. If Rotom changes to its base form, it forgets the special move of the form it was in (if it still knows it); if the only move that Rotom knows right before reverting to its base form is the form's special move, then that move will be replaced with Thunder Shock.
Rotom has five alternate forms it can change between, in addition to its default form. To take on these alternate forms, Rotom possesses a different household appliance, and each has its own special move. These alternate forms were introduced in Pokémon Platinum.
In Generation IV, all forms of Rotom are Electric/Ghost-type; from Generation V onward, the appliance forms replace the Ghost type with the type of their associated move. All appliance forms have the same base stats, with a higher total than that of Rotom's default form; the only base stat of normal Rotom that is higher than its appliance forms is its Speed.
Using these locations, Rotom can also return the appliance to change back to its default form. In Generation IV, Rotom changes back to its default form when taken into the Union Room or Wi-Fi Club, or when deposited in the Pokémon Day Care.
Hatched Rotom will always be in their standard form.
Upon changing into an appliance form, Rotom will learn the special move associated with the form, and upon changing from an appliance form, it will forget that special move. When changing forms, if Rotom knows four moves but not the special move of its previous form, the player will be prompted to replace a move with the new exclusive move (Rotom cannot change to an appliance form unless it does). If Rotom's only known move is its special move and it changes to its default form, then the Rotom will learn Thunder Shock. In Generation IV and Generation V, if Rotom forgets the move that is tied to its appliance form, it changes back into its default form. Starting in Generation VI, Rotom can remain in an appliance form even if it forgets the associated special move.
Rotom's appliance forms first appeared as silhouettes in August 2008, shortly before the Japanese release of Pokémon Platinum, with a statement that indicated that these Pokémon would be in the game. Days before the game's release, it was revealed that these Pokémon were the alternate forms of Rotom. These new forms made their debut in Pokémon Platinum, and have been included in every core series game since.
In Generation IV, there are five separate appliances and changing Rotom's form temporarily removes that appliance from the room, so the player can never have more than one of each form. From Generation V onward, this limitation is removed. In Hisui, five separate appliances are again depicted, but changing Rotom's form does not remove that appliance from the room.
Rotom is the only Pokémon to have its type changed to a type that was not newly introduced.
No other Pokémon has the same typecombination as Rotom's base form or Heat Rotom, making Rotom the only Pokémon with more than one unique type combination.
Despite becoming part Flying-type, Fan Rotom retains the AbilityLevitate, being the only Flying-type Pokémon with this Ability. As its Flying type already makes it immune to Ground-typemoves, its Ability is effectively useless under normal conditions.
In Inverse Battles, Fan Rotom is still protected from Ground-type moves due to Levitate, making it the only Flying-type Pokémon to not be affected by Ground-type moves in these battles by default.
All of Rotom's appliance forms (except Mow Rotom) are tied for or have the fewest weaknesses of all Pokémon of their secondary types.
All of Rotom's alternate forms (except Mow Rotom) are also the lightest Pokémon of their secondary typing.
Each of Rotom's forms takes its appearance after an electronic object with arms made out of electric sparks. Its regular form seems to be based on a light bulb, Heat Rotom possesses an oven, Wash Rotom a washing machine, Frost Rotom a refrigerator, Fan Rotom a fan and Mow Rotom possesses a lawnmower.
Rotom is derived from motor spelled backwards.
In Pokémon Platinum, an old notebook in Rotom's Room describes how a person discovered and named the first known Rotom. It appeared out of a lawn mower's motor, and the person named it Rotom due to this origin.