EVs, IVs, and all that other crap, how does it work?

[Dude]

I never really understood it, so could someone please explain it to me?

All I know are that IVs are hidden and EVs are earned, but that's about it.

[Shadoninja]

IV=Individual Value
these are set unchangeable numbers that affect the stats of a pokemon. they go up to 31.
EV=Effort Value
these can be modified. for every 4 EVs you get in a stat, that stat goes up by 1 when you level up. you can have a total of 510 EVs overall and 255 per stat.

[DrP]

You get EVs when you defeat a Pokémon, and it depends on the Pokémon's evolution. Some Pokémon give 1 EV and others give 2 or 3 EVs IT depends on the Pokémon on which EVs are given, so consult Serebii or Bulbapedia for guidance on this matter.

[Dude]

Ok... Now if I catch a pokemon, will it's EVs be 0 on all stats?

[Shadoninja]

yep

[Dude]

So if I haven't EV trained a pokemon and I now want to, how can I lower the EVs to start fresh?

[Shadoninja]

certain berries.
Pomeg Berry = Lowers HP EVs
Kelpsy Berry = Lowers Attack EVs
Qualot Berry = Lowers Defense EVs
Hondew Berry = Lowers Special Attack EVs
Grepa Berry = Lowers Special Defense EVs
Tamato Berry = Lowers Speed EVs

[Dude]

Now where can I get them in White?

[Roz~]

Not sure you can.

Also, here is some stuff you should know too.

Pokémon can have a maximum of 510 EVs which can be split among HP, Atk, Def, SpAtk, SpDef and Speed.
EVs are factored into the Pokémon's stats when it levels up in generation I-IV.
In Gen V, they are recalculated after every battles, which means lvl 100 Pokémon can now gain EVs too.

Natures also play a role in determining your Pokémon stats, as they usually increase one stat by 10% and decrease another one by 10%.
Timid nature is + Spe - Atk, Adamant is + Atk - SpAtk, etc.


IVs are, as you mentioned, hidden stats. They go from 0 to 31, 31 being the highest you can get. They basically are responsible for the variation you can see in stats among Pokémon, i.e 2 Rattatas having different stats for example.
They determine the max stat you can get.
1 IV = 1 stat point.
If one of your Pokémon has 27 IVs in his Atk stat, then he's 4 points short to have max Atk.
They also determine a Pokémon's Hidden Power type. 31/31/31/31/31/31 gives HP Dark 70, while 30/31/30/31/30/31 gives HP Ghost 70.

[Dude]

I get the rest and all but,

In Gen V, they are recalculated after every battle, which means lvl 100 Pokémon can now gain EVs too.

This part confuses me.

[Roz~]

Basically, EVs are taken in consideration when your Pokémon levels up in gen 1-4. So if you EV train your Pokémon, usually you'll get something like +14 in one stat. But in Gen 5, instead of being factored in when your Pokémon levels up, they are factored in after every battle. Lvl 100 Pokémon couldn't get any EVs because they can't level up anymore; that's why they now can in Gen 5.

[Dude]

...So the stat is always changing? Weird.

[Roz~]

Yea, kinda. Also Pokérus is win when you EV train.

[Dude]

So wait, it doesn't matter when you EV train? If so, that's awesome.

[Roz~]

wat