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Pokémon natures are a factor in a Pokémon's stat growth. Natures boost development of one stat but inhibits the growth of another stat. A Pokémon's nature also affects what Pokéblock flavor it likes the most.

Nature	Attack	Defense	Special Attack	Special Defense	Speed	Likes	Dislikes
Adamant	Rises Quickly		Rises Slowly			Spicy	Dry
Bashful
Bold	Rises Slowly	Rises Quickly				Sour	Spicy
Brave	Rises Quickly				Rises Slowly	Spicy	Sweet
Calm	Rises Slowly			Rises Quickly		Bitter	Spicy
Careful			Rises Slowly	Rises Quickly		Bitter	Dry
Docile
Gentle		Rises Slowly		Rises Quickly		Bitter	Sour
Hardy
Hasty		Rises Slowly			Rises Quickly	Sweet	Sour
Impish		Rises Quickly	Rises Slowly			Sour	Dry
Jolly			Rises Slowly		Rises Quickly	Sweet	Dry
Lax		Rises Quickly		Rises Slowly		Sour	Bitter
Lonely	Rises Quickly	Rises Slowly				Spicy	Sour
Mild		Rises Slowly	Rises Quickly			Dry	Sour
Mild	Rises Slowly		Rises Quickly			Dry	Spicy
Naive				Rises Slowly	Rises Quickly	Sweet	Bitter
Naughty	Rises Quickly			Rises Slowly		Spicy	Bitter
Quiet			Rises Quickly		Rises Slowly	Dry	Sweet
Quirky
Rash			Rises Quickly	Rises Slowly		Dry	Bitter
Relaxed		Rises Quickly			Rises Slowly	Dry	Sweet
Sassy				Rises Quickly	Rises Slowly	Bitter	Sweet
Serious
Timid	Rises Slowly				Rises Quickly	Sweet	Spicy