While finding a clean file can be a hassle due to dead links and fake malware sites, the result is magical: permanently installing the best Sinnoh experience directly onto your 3DS home menu.
For many fans, Pokémon Platinum represents the pinnacle of the "Golden Age" of Pokémon. Released in 2008 for the Nintendo DS, it took the already solid foundation of Diamond & Pearl and fixed pacing issues, expanded the Pokédex, and introduced the disturbing yet captivating Distortion World.
Power off your 3DS. Remove the SD card and insert it into your computer. Copy the .cia file into a folder you remember (e.g., /cias/ ). Eject the SD card.