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 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 electrocuted in the process.
Rotom and the appliances
Rotom has the ability to enter and control appliances. Starting in Platinum, it has five extra forms, which 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 form, 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. According to the Rotom Catalog, Rotom in its base form is actually possessing a light bulb.
Rotom's forms were known to have been first discovered and documented by Charon, despite the fact that Rotom existed in Hisui and was also documented in the ancient 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.
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 Rotoms 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 seen in the anime, Rotom also has the ability to time travel. Rotom tends to reside in abandoned buildings. Research continues on Rotom and its ability to power unique motors.
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 a double dagger (‡) can only be bred from a Pokémon who learned the move in an earlier generation.
Moves marked with a superscript game abbreviation can only be bred onto Rotom in that game.
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 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.
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.