What does the Naughty nature do?

Naughty raises Attack by 10% and lowers Sp. Def by 10%.

What stat does Naughty increase?

Naughty increases Attack by 10% and decreases Sp. Def by 10%. HP is unaffected.

A Naughty Pokémon likes Spicy flavors (tied to Attack) and dislikes Bitter flavors (tied to Sp. Def).

Yes. Use a Naughty Mint to apply the Naughty stat effect to any Pokémon without changing its displayed nature.

Nature

Raises Attack, lowers Sp. Def.

Raises Attack +10%

Lowers Sp. Def −10%

LikesSpicy

DislikesBitter

Physical attackers on offense-heavy teams that won't take special hits.

Lonely −Defense Brave −Speed Adamant −Sp. Atk

What does the Naughty nature do?: Naughty raises Attack by 10% and lowers Sp. Def by 10%.
What stat does Naughty increase?: Naughty increases Attack by 10% and decreases Sp. Def by 10%. HP is unaffected.
What flavor does a Naughty Pokémon like?: A Naughty Pokémon likes Spicy flavors (tied to Attack) and dislikes Bitter flavors (tied to Sp. Def).
Can I change a Pokémon to Naughty?: Yes. Use a Naughty Mint to apply the Naughty stat effect to any Pokémon without changing its displayed nature.