As a Pokémon expert with extensive knowledge of the franchise's lore, I can confidently address the classification of Rotom within the Pokémon universe.

Rotom is not considered a legendary Pokémon. Legendary Pokémon are typically characterized by their great power, rarity, and often a story or myth surrounding their existence. While Rotom is a unique and rare Electric/Ghost-type Pokémon, it does not fit the traditional criteria for being a legendary Pokémon. Rotom is known for its ability to possess and reside in various electronic devices, which is a distinctive feature that sets it apart from other Pokémon. However, it is categorized as a "Mold Pokémon" in the games and is not grouped with the legendary Pokémon.

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Rotom is not a legendary Pokemon, because you can breed it with Ditto to get more Rotom. Also, its stats aren't in the range that legendary Pokemon typically get.read more >>