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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	Favorite	Least Favorite
Adamant	Rises Quickly		Rises Slowly			Spicy(Cool	Dry(Beauty)
Bashful
Bold	Rises Slowly	Rises Quickly				Sour(Tough)	Spicy(Cool)
Brave	Rises Quickly				Rises Slowly	Spicy(Cool)	Sweet(Cute)
Calm	Rises Slowly			Rises Quickly		Bitter(Smart)	Spicy(Cool)
Careful			Rises Slowly	Rises Quickly		Bitter(Smart)	Dry(Beauty)
Docile
Gentle		Rises Slowly		Rises Quickly		Bitter(Smart)	Sour(Tough
Hardy
Hasty		Rises Slowly			Rises Quickly	Sweet(Cute)	Sour(Tough)
Impish		Rises Quickly	Rises Slowly			Sour(Tough)	Dry(Beauty)
Jolly			Rises Slowly		Rises Quickly	Sweet(Cute)	Dry(Beauty)
Lax		Rises Quickly		Rises Slowly		Sour(Tough)	Bitter(Smart)
Lonely	Rises Quickly	Rises Slowly				Spicy(Cool)	Sour(Tough)
Mild		Rises Slowly	Rises Quickly			Dry(Beauty)	Sour(Tough)
Mild	Ries Slowly		Rises Quickly			Dry(Beauty)	Spicy(Cool
Naive				Rises Slowly	Rises Quickly	Sweet(Cute)	Bitter(Smart)
Naughty	Rises Quickly			Rises Slowly		Spicy(Cool)	Bitter(Smart)
Quiet			Rises Quickly		Rises Slowly	Dry(Beauty)	Sweet(Cute)
Quirky
Rash			Rises Quickly	Rises Slowly		Dry(Beauty)	Bitter(Smart)
Relaxed		Rises Quickly			Rises Slowly	Dry(Beauty)	Sweet(Cute)
Sassy				Rises Quickly	Rises Slowly	Bitter(Smart)	Sweet(Cute)
Serious
Timid	Rises Slowly				Rises Quickly	Sweet(Cute)	Spicy(Cool)