Rotom Pokemon BDSP
Image: Nintendo Life

Pokémon Brilliant Diamond and Shining Pearl gives eager fans the chance to jump back into the Sinnoh region for the first time since the original Nintendo DS versions, and there are a few favourite Pokémon they’ll be keen to pick up straight away. Some Pokémon from generation 4 require a bit more patience, though — Rotom, a unique Pokémon in the sense that it can change into several forms, is one of them.

In this guide we’ll show you how to get Rotom and how to make it change forms.

How to get Rotom in Pokémon Brilliant Diamond and Shining Pearl

Complete the Sinnoh Dex

Firstly, you’ll need to complete the Sinnoh Pokédex. Thankfully, this can be done with one copy of the game, and in one playthrough. All you need to do is to see one of every Pokémon, not catch them, and this can all be achieved during the course of the normal game.

If you’re struggling to see the box legendary of the other copy, Dialga or Palkia, speak to Cynthia’s grandmother and she’ll show you it.

After that, head back to Professor Rowan and he’ll upgrade your Pokédex for you, allowing you to catch almost 500 Pokémon in total, including plenty of new legendaries.

Old Chateau

Head to Eterna Forest and go to the Old Chateau, which is located near the top of the zone. You can use Cut to get into the area, then walk up to the building.

In the Old Chateau, on the second floor, there’s a room with a TV. Interact with the TV and you’ll battle Rotom. It’s only level 15, so one ultra ball should do it. Once you’ve captured Rotom, you’ll find a secret key in the same room, this key is vital to the next step.

Eterna City Galactic HQ

Take Rotom and the key to Galactic HQ in Eterna City. On the bottom floor, all the way to the left there’s an area you can interact with which will suddenly open, revealing a new room. Head inside and you’ll be presented with a room full of appliances.

These appliances change Rotom’s forms, and interacting with all of them will add to your Rotom Catalogue item, which can make Rotom change between those forms without having to come back to this building. It’s a shame you can’t do this earlier in the game, but it’s still a unique Pokémon to pick up towards the end of your journey.

Rotom has five forms, Heat Rotom, Frost Rotom, Mow Rotom, Wash Rotom and Fan Rotom. Each of these forms is a different type, making it one of the most versatile Pokémon in the game.

This article is part of our Pokémon Brilliant Diamond and Shining Pearl walkthrough and guide series, which includes every version-exclusive Pokémon in each version of the game, advice on the best Sinnoh starter Pokémon to choose, and all the old and new Pokétch Apps, plus how to get specific Pokémon such as Mew and Jirachi, Rilou and Lucario, Manaphy and Phione, Arceus, Eevee, Leafeon And Glaceon, Cresselia, Rotom, Ditto, Spiritomb, Heatran, Regigigas, and — of course — the mighty Feebas.

We also cover how to catch 17 Legendaries in Ramanas Park, where to find the Defog HM and chain catching (or how to increase your chances of catching Shiny Pokémon), plus how to earn money fast, how to beat the Elite Four, how the Trophy Garden works, and how to get the DS sounds and Catching Charm. We also have a full and updated list of Pokémon Brilliant Diamond and Shining Pearl Mystery Gift codes, plus we tell you how to unlock the Mystery Gift function, too.

And finally, Where to Buy Pokémon Brilliant Diamond and Shining Pearl on Nintendo Switch, if for some reason you haven't yet picked up the game!