"EV" stands for Effort Value. This value can be increased to raise stat points through something called "ev training". EV training is really simple. All you need is an exp all that is on which I'm sure you have, if you don't it is available at /warp shop. You will need 1 of each of the power items as well.
Power Weight (green) - HP
Power Bracer (red) - Attack
Power Belt (orange) - Defense
Power Lens (purple) - Special Attack
Power Band (yellow) - Special Defense
Power Anklet (blue) - Speed
So the pokemon at " /warp grinder " 's ev station each give 3evs to the stat that their area is labeled.
Clefable - HP
Luxray - Attack
Poliwrath - Defense
Vileplume - Special Attack
Politoed - Special Defense
Raichu - Speed
put the correct power item on the pokemon you want to ev train that stat in. for example, I'll have a level 100 tyranitar in slot 1 to defeat the pokemon and I'll have a level 1 pikachu with no evs atm in slot 2 holding a power anklet. I'll make sure my exp all is on and then I'll go defeat a raichu with my tyranitar. Then when I do " /evs 2 ", I'll notice that my pikachu now has 7 speed evs. This is because the Raichu I defeated gives 3 speed evs and the power anklet gives 4 speed evs no matter what pokemon is defeated (so if I was to defeat a vileplume in this example instead I'd gain 3 special attack evs and 4 speed evs instead).
Why ev training is good is because for every 4 evs a pokemon has in a stat, that's 1 more additional stat point. Since a pokemon can have up to 255 evs in a single stat, that's up to 62 additional stat points. For example I have two different Tyranitar sets. One is ev trained in hp and has 404 hp, the other isn't and only has 342.
The most common ev spreads are 252 in one stat, 252 in another stat and 4 in a third stat. That's because 255 isn't divisble by 4, but 252 is. ( I forgot to mention a pokemon can only have 255 evs in a single stat max and 510 evs across all stats max ). So if you do this ev spread, it maximizes the amount of stat points gained. While ev spreads like these aren't always optimal, it's a good place to start for beginners.
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Since 252 is divisible by 7 (the amount of evs you'll be getting per kill), that means you have to defeat 36 of that pokemon with the corresponding power item to hit 252. An easy way to keep track of this is keeping track of the PP of the pokemon you're using to kill the pokemon at the grinder. For my Tyranitar example 15 crunch + 20 pursuit = 35 kills. I then just need one more kill after that to fully ev train a stat. Easy right?
"I wish I would have known about all this before, my pokemon has messed up evs. What can I do?"
Well, lucky for you, the server has thought of that. Do " /warp grinder " and take the stairs that say "EV RESET" (they're on the left). Make sure you step on the pressure plates labeled of the correct slot matching the pokemon whose evs you want to reset and they will be reset to 0.
"Oh no, I wasn't paying attention and my pokemon's ev hit 255 instead of 252, do I have to reset and start from the beginning?"
No, again this was thought of as well. Simply go down the hallway of the ev station and buy the corresponding berry to the stat you went over. They cost 1000 each, so try not to need them too often. These berries lower their specified ev by 10 points. This makes the math line up perfectly because you will go from 255 to 245 meaning you only need 7 more to hit 252 which as we said is just one battle.
Pomeg Berry - Reduces HP evs by 10
Kelpsy Berry - Reduces Attack evs by 10
Qualot Berry - Reduces Defense evs by 10
Hondew Berry - Reduces Special Attack evs by 10
Grepa Berry - Reduces Special Defense evs by 10
Tomato Berry - Reduces Speed evs by 10
Find my breeding guide here.