How does a nature affect stat growth?

Question

I am EV training a Dialga (From the event) for Special Attack. It holds a Power Lens (Or whatever that SP attack power item is) and i'm battling against Pokemon that give one EV sp attack. It has a Careful nature, but each time it battles it SP attack goes up one. Am I getting 4 1/2 EV's for each battle?

Answer 1

Power Lens will add 4 Sp. Atk to any Pokemon defeated (not just ones that give out sp. atk EVs), and since you're fighting Pokemon that give 1 Sp. Atk EV each, you're getting 5 EVs per battle, not 4.5.

A Careful nature does not mean you're get 4.5 EVs per battle. What the Careful nature means is your Dialga's sp. atk is 10% less than what it should be if it had a neutral nature regardless of EVs, and EV gain is not affected by natures.

Answer 2

Natures raise a stat by 10% and lower one by 10%. You are still getting the EVs, 5 to be exact from what you said there, but at level 100, it still might be low since careful lowers Special Attack.

Hope this helps!