You've probably heard the term "effort values" used before. Effort values, shortened to EVs, are very important when it comes to training Pokemon for competitively battling as it allows Pokemon to excel in certain stats. EVs are not entirely important when it comes to casual battling or just completing the game, although they will certainly make some battles easier for you.

In Generation I (Red, Green, Blue and Yellow versions), whenever a Pokemon was defeated in battle, whether it was in a wild battle or a trainer battle, it would give out effort points along with experience points to the Pokemon that defeated it. The number of effort points a Pokemon gave out was between 1 and 3. That number was then assigned to a certain stat. The effort points and the stat the points went to were constant for each Pokemon. For example, defeating a Golem would yield 3 effort points for defense; Golem would never yield for anything other than defense. Only Pokemon that were sent out into battle gained those points.

For every four effort points gained towards a certain stat, that stat would increase by 1 whenever the Pokemon leveled up via experience points. For example, if your Staryu fought four Golems, you would gain 12 effort points for defense. When Staryu gained enough experience points and leveled up, its defense stat would increase by 3 more points than it would have if you had not fought four Golems.

At level 100, though it stops increasing in level, a Pokemon can still gain effort points. This means that a Pokémon’s stats can still continue to grow. In order for this to be done, a Pokemon must be deposited into the PC and then withdrawn. This causes the game to recalculate the effort points and reflect it upon the stats, as if the Pokemon had leveled up. Potentially this means that a Pokemon could have stat values of 999.

Vitamins made their debut in the first generation. Using these vitamins would increase one stat by a certain amount of points.

In Generation II (Gold, Silver and Crystal) the system remained the same. However, the Pokerus concept was introduced. This was a virus that infected your Pokemon. A Pokemon that had the virus would have it for roughly twenty-four to forty-eight hours before it disappeared. In the meantime, any Pokemon in your party would get infected with the virus. A Pokemon that had the virus would not spread it if it was put in the PC; any Pokemon already in the PC could not get it.

The benefit of the Pokerus was that the effort points Pokemon gave out were doubled. Instead of Golem giving 3 points to defense, it would now give out 6. Basically it reduced the amount of Pokemon you had to fight; instead of fighting four Golems to get +3 defense, now you would only have to fight two.

In Generation III (Ruby, Sapphire, FireRed, LeafGreen and Emerald), the system was completely overhauled. Pokemon no longer gave out effort points, and instead, gave out effort values. Same concept though.

Like in the first two generations, any Pokemon could gain an infinite amount of effort points; however, there was a catch: only 512 of those points would actually effect stat growth and one stat could only get 255 of those points. Essentially, only one two stats could be maxed out, although some trainers like to spread them out.

For example, let’s use Golem. Let’s say you battled 333 Golems and as a result, gained 1000 effort values for defense. The games would only take into account 255 of those points, meaning the other 745 are wasted. However, the games may only calculate 100 or maybe even 4 of those points depending on how you’ve distributed the 512 points up until this point.

To compensate for this somewhat, natures were introduced. Natures would determine stat growth. Under natures, one stat would be exceptionally higher than the others, while one stat would be exceptionally lower. For example, a Pokemon with the Adamant nature will have a higher attack at the cost of having lower special defense. A Pokemon with this nature will gain more to its attack regardless if it gains EVs, although the extras help.

The Pokerus returns as well and is restricted to the 512-point clause. It makes getting there a little faster. In addition to that, an item called the Macho Brace was included. Like the Pokerus, it doubled the EV points gained. So let’s say you battled one Golem with a Pokemon infected with the Pokerus and is holding the Macho Brace. Instead of gaining 3 points, your Pokemon would gain 9 effort points to defense.

Earlier it was mentioned that in Generation I and II, a Pokemon deposited into the PC and withdrawn would have its effort values recalculated to reflect onto the stats. The same thing applies to Generation III; however, this will only work on Pokemon up to level 99 and the Pokemon is still bound by the 512 point maximum.

The vitamins that once gave increases to stats were changed. Instead of directly affecting the stats, they would simply add 10 effort points to that stat. Each stat could gain 100 effort value points this way. After gaining 100 points, the Pokemon will refuse to take any more.

Special berries were also introduced. When used, a Pokemon would lose 10 effort points to a stat which allowed the trainer to put those 10 points to another stat, given it hadn’t reached the 255 or 512 clause limit.

In Generation IV (Diamond, Pearl and Platinum) the system remained the same. Several new items were introduced that were similar to the Macho Brace of Generation III. Instead of doubling points, it simply gave them to the Pokemon holding the item regardless of what effort points the wild Pokemon would give out.

For example, let’s say you encounter a wild Shinx. Shinx gives out 1 point to attack. Your Pokemon is holding the Power Belt. Your Pokemon would gain, if it defeated the wild Shinx, 1 point to attack and 4 to defense. If you remember what I stated earlier about how the system works, you would automatically get +1 defense every time you defeat wild Pokemon as long as your Pokemon held the Power Belt item. This is even affected by the Pokerus virus. Rather than gain +1, you would now gain +2 in addition to the attack EVs Shinx would give out.

Now for more in-depth information about effort values…

The rarity and size of the evolution family determines how many points a Pokemon will give out. Some Pokemon, especially in later generations, give out points to multiple stats, although the total always adds up to 3.

If the evolution family consists of three stages (example: Charmander, Charmeleon, Charizard), the first stage Pokemon always gives out 1 point, the second stage Pokemon gives 2, and the third and final member gives out 3. More often than not, the points always go to the same stat, although there are a few exceptions to this.

If the evolution family consists of only two stages (example: Rattata, Raticate), then rarity comes into play. If the first stage Pokemon is common, then it will give out 1 point; its evolution will then give out 2. If the first stage Pokemon is uncommon or rare, then it will give out 2 and its evolution will give out 3.

Legendary Pokemon always give out 3 points. Pokemon that do not evolve are then compared in strength to other Pokemon; for example, Ditto, despite being rare, only gives out 1 point because its power is comparable to Rattata.

The stats affected by the Pokemon effort values are largely determined by the nature (not the one mention above; think behavior and Pokedex entries) and appearance of the Pokemon. This is a typical generalization, meaning “I looked at these groups and these are the common traits I seen.” Not all Pokemon listed (such as in appearance or type) share these traits, but other members of their type do.

Typically, a Pokemon that is said to be powerful, smart or violent typically give effort values for attack and special attack. Pokemon like this include Tyranitar, Alakazam and Houndoom. Typically, the types of Pokemon that give out attack and special attack points are Normal, Fire, Water, Fighting, Dark, Psychic and Ghost.

Pokemon that are said to be fast by nature, or appear streamlined or lite, give out points for speed. Pokemon like Jolteon, Starmie and Aerodactyl give out points for speed. Typically these Pokemon are off the Flying, Poison, Bug and Electric types.

If a Pokemon appears fat, bulky or generally tough, it is a sure sign that the Pokemon gives out defense or special defense points. Snorlax, Rhyperior and Steelix are examples of this. Typically, Pokemon of this nature are Grass, Ice, Rock, Ground and Steel.

So why does effort values matter? Well, if you aren’t a competitive battler, they don’t mater. But if you are, they determine everything.

Some Pokemon are more inclined, due to nature, to have better stats than others. Effort values help the trainer make that stat (or stats) as high as it can be so it can be better than other Pokemon

For example, all Tyranitar have great attack, not so great special attack, modest defenses but shitty speed. Tyranitar, despite having massive attacking power, is useless if cannot hit first. As such, a trainer would find a Tyranitar with a nature that favors speed or attack, and that trainer would make Tyranitar battle Pokemon that gave out speed EVs to boost its speed. Special attack would most likely be ignored. However, with a Pokemon Alakazam, the trainer would want to focus on the Special Attack stat.

So basically, if you wanted your Pokemon to have better speed compared to other Pokemon of its species or to other Pokemon, you would fight Pokemon that gave out speed EVs. You would get +1 to your speed at level up with every four speed points you gained.

Again, it takes 4 effort points to total 1 stat point. In earlier generations, you were not limited to the amount of effort points you could get. In newer generations this has changed the limit it capped, so you have to consider what stat you want your Pokemon to specialize in, which is often predetermined by the Pokemon itself.

Below are the various categories in which effort points may be obtained. The following pages (which at this point are in development) will list all the Pokemon effort values to those stats. If you clicked on HP, it would show you Pokemon that gave out EVs for HP sorted by how much they gave out.