Pokemon stats explained! EVs, IVs, Natures, everything! PLEASE READ!
What if I don't like the way my EVs are arranged? Can I remove them?
First of all, one of the punching bags you can get from Super Training is a solid-white Reset Bag. Any Pokemon that punches this will have all of their EVs sent back down to zero.
You can do the same thing by mixing a Perilous Soup at the Juice Shoppe. This requires one Kee and one Maranga Berry.
If you just want to fine tune them a little, there are certain berries that reduce an EV by 10. These berries are:
Special Attack: Hondew
Special Defense: Grepa
Removing your EVs will also lower your stats, so you can't abuse the system. But it lets you retry a bad spread.
EVs never disappear from your Pokemon unless you do one of the above; they are otherwise permanent. Gaining levels, evolving, trading; none of this affects EVs.
How can you check how many EVs you have?
Super Training has a hexagon-shaped chart that will give you a rough idea. The yellow region represents your EVs. Too vague? You can do better.
Save first. Did I mention save? You'll be sorry if you don't! So, now that you've completely saved...
Punch a Reset Bag.
This removes all EVs from a Pokemon, and as it does so it will show exactly how those EVs are changing on the hexagon grid. So if you see see a -120 next to a stat, that means your Pokemon had 120 EVs in that stat.
And now doesn't any more, so unless you really wanted to remove the EVs, you'd better reset!
How do I know which stats I should train in?
It's completely up to you! Sites like Smogon give suggested EV builds, but you don't have to follow them. I'll just say this: most people train offensive Pokemon in Speed and the Attack stat they use, while defensive Pokemon usually get HP and the lower Defense boosted, unless its HP is high enough relative to the defenses. But I have no gun to your head. Experiment!
When should I start training the Pokemon? At level 1?
Doesn't matter. But if the Pokemon has seen battle already, it may have EVs you don't want, so you'll want to erase those first.
How many EVs should I get per level?
Doesn't matter. EVs are not given on a per-level basis. EVs are EVs and levels are levels.
Are EVs why Rare Candies are bad?
Rare Candies are not bad. There is no negative side effect to using Rare Candies.
So if I get 4 EVs, that means I'll get 1 point of stat gain when I level up?
No, that's not how it works. There is no such thing as "stat gain" in Pokemon, at least not of the Fire Emblem sort. The Little Plus Numbers (LPNs) you see when you level up don't mean anything of value and can be safely ignored.
And that's not dodging the question. It's not at all impossible to receive a +0 LPN in a stat you've been training, especially in the later generations where EVs are applied to your stats immediately after you get them.
I trained up to 252 EVs in Super Training, but my level 20 Pokemon barely has 63 in its stat at all, let alone from EVs! What gives?
The 63 point boost from having 252 EVs kicks in only at level 100. At level 20, you'll only get 12 or 13 points in a Nature-neutral stat from 252 EVs. Don't worry, those EVs will still be in all their 63-point glory there once you've hit level 100!
Can I gain EVs at level 100?
You can't through battle in the third or fourth generations. In any other generation (including, sort of, the first two, though the system was quite different then), yes, you can EV train through any method at level 100.
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