Effort value

Effort values (Japanese:  effort values), abbreviated EVs, are attributes which give bonuses to an individual Pokémon's stats and improve differently depending which Pokémon they defeat. Officially, they have been referred to as  base points in Japanese since and as base stats in English since.

In the context of Generations I and, the effort system is unofficially known as Stat Experience, or "Stat Exp." for short.

Effort values only appear in the core series and side series Pokémon games; they are not present in the spin-off Pokémon games, such as the Pokémon Mystery Dungeon series.

Effort values, in the form of effort points, are gained in addition to bonuses gained by increasing level. Effort values usually make trained Pokémon stronger than wild Pokémon, even those of the same level. Effort points are awarded equally to all Pokémon who participated in defeating a Pokémon. Though they are shared, each of the Pokémon will receive the standard amount of effort points.

Prior to Generation VI, there is no way to directly view effort values; from Generation VI onward, it is possible to view graphs that show effort values without giving specific numbers. Shigeru Ohmori has stated that the reason EVs and s are hidden is because he prefers to think of as "real, living creatures".

Measuring EVs
Vitamins,, and wings all change a Pokémon's EVs until a limit is reached. They raise a stat by 10 EVs until it reaches 100, lower a stat by 10 EVs until it reaches 0, and raise a stat by 1 EV until it reaches 255, respectively. The amount of items that a Pokémon can consume is proportional to the number of EVs it has in its respective stat. For example, a Pokémon that can eat two Pomeg Berries before its HP stops decreasing has between 11 and 20 EVs in HP.

If a Pokémon has the maximum 510 effort points, it can receive an (Generation III,, , and ). This Ribbon will remain on the Pokémon even if its EVs are lowered such that it does not have 510 effort points.
 * In, a non-playable character (NPC) in the will give the player's Pokémon an Effort Ribbon.
 * In, an NPC in the Sunyshore Market will give the player's Pokémon an Effort Ribbon.
 * In, an NPC in Blackthorn City will give the player's Pokémon an Effort Ribbon.
 * In, an NPC in the Laverre City Pokémon Fan Club will give the player's Pokémon an Effort Ribbon.
 * In, an NPC in the will give the player's Pokémon an Effort Ribbon.
 * In, , an NPC in the Battle Royal Dome will give the player's Pokémon an Effort Ribbon.

In, there is an NPC in a house in Opelucid City who will tell the undefined if the Pokémon at the front of his or her party has attained 510 total effort values.

In Pokémon Black 2 and White 2, Bianca, when called on the Xtransceiver after the player has defeated the, will tell the player whether a certain Pokémon in the party has attained 510 total effort values. She will also notify the player if a Pokémon has reached 252 effort values in any stat.

In Pokémon X and Y and Pokémon Omega Ruby and Alpha Sapphire, Super Training can be used to numerically determine the effort points of a Pokémon. Additionally, a Pokémon will be marked as a Fully Trained Pokémon if it has 510 effort values.

In, , pressing the Y button on a Pokémon's Summary screen will show an orange graph depicting the EVs it has accumulated so far; stats that have reached 252 effort values will sparkle. When the Pokémon has reached the maximum amount of 510 EVs, the graph will turn cyan.

Stat experience
In Generations I and, effort points given are equal to the base stats of the defeated Pokémon species.

The Pokémon data structure contains two EV bytes for each of the five stats (HP, Attack, Defense, Speed and Special), starting at zero when caught and with a maximum EV of 65535 for each stat. When a Pokémon is defeated, its base stats are converted to effort points and then added to the EVs. For example, defeating a grants 100 effort points to each EV. (Defeating 656, therefore, will give a Pokémon maximum EVs in each stat.)

EVs are factored into the Pokémon's stats when it levels up. Additionally, EVs are calculated into stats when a Pokémon is taken from Bill's PC; this is called the box trick. A Pokémon which reaches level 100 can continue to acquire EVs up to the maximum of 65535 in each stat, and use the box trick to have those EVs factored in.

Vitamins add 2560 to one stat's EV, but cannot raise a stat above 25600.

At level 100, the formula for determining the stat difference between a Pokémon trained in that stat and an untrained Pokémon is, with the square root rounding upwards unless that would take it above 255, and the whole calculation rounding downwards.

EVs behave the same in Generation II as they did in Generation I. Both Special Attack and Special Defense share the EV for Special to maintain compatibility. The amount of Special EVs received is equal to the defeated Pokémon's Special Attack base stat. The box trick can still be used.

Generation II introduced the Pokérus, a rare status condition which doubles the effort points gained in battle.

Modern system
Since Generation III, effort points have been completely separate values from base stats. Defeated Pokémon give out 1, 2 or 3 effort points to a particular stat, depending on species (see list of Pokémon by effort value yield). However, in battles that do not give any experience (such as in the or if the Pokémon is level 100), Pokémon will not gain any effort points. At level 100, a Pokémon's stats will be one stat point higher in a specific stat for every four effort points gained in that stat.

Pokémon are limited to 510 effort points in total. Since Generation III, because stats are calculated by dividing effort by 4 and disregarding the remainder, 252 effort points are required to maximize a stat. As a result, the maximum amount of additional stat points that can be acquired by EV-training for a given stat is 63 when the Pokémon is level 100, in comparison to an otherwise identical Pokémon that is uninvested in EVs (and ignoring natures).

Vitamins add 10 effort points, but cannot raise a stat above 100 EVs, or raise the total above 510. These Vitamins can be found for 9,800 in department stores or in Laverre City in Generation VI, and for 10,000 at Mount Hokulani in Generation VII. The list of Vitamins include:

If a Pokémon holds an Exp. Share, it will receive effort points even if the battling Pokémon has maxed out its effort points. If the Pokémon with the Exp. Share has Pokérus, the amount of effort points received is doubled.

The Macho Brace doubles the effort points gained in battle. In combination with the Pokérus, a Pokémon can gain four times the normal effort points. However, the effects of the item do not transfer to a Pokémon holding an Exp. Share.

Generation III
From generations III to, Pokémon are limited to a total of 255 effort points per stat, and 510 effort points in total. In Generations III and, Pokémon recalculate their stats upon leveling up, except for , whose stats are recalculated after every battle instead. Stats are also recalculated immediately if a Vitamin or stat-reducing Berry (see below) is used on the Pokémon.

Starting in, certain Berries that were previously only used to make Pokéblocks can decrease certain effort values by 10 effort points, while increasing the friendship of the Pokémon they were used on. The game will tell the player if the Pokémon's friendship cannot increase or if the stat does not decrease. These Berries are:

In, Shadow Pokémon do not earn effort values from battling until they have been purified, although vitamins can still be used on them.

Generation IV
Most of the Generation IV EV system remains unchanged from Generation III. However, EV-reducing Berries will reduce Effort Points to 100 if the current Effort Points for the stat were above 100.

A new series of items exist which give an additional four effort points per Pokémon defeated. Each applies the bonus to a different stat, in addition to the normal effort points gained. The bonus effort points are also doubled by the Pokérus. The effects of these items do not transfer over to a Pokémon holding an Exp. Share.

If a Pokémon has alternate forms that change its stats (e.g. ), any effort points acquired will be applied to its stats when the form is changed, allowing the player to boost their Pokémon's stats without having to level it up.

Generation V
In Generation V, most of the EV system remains unchanged from Generation and.

EV-reducing Berries no longer reduce Effort Points to 100 if the points were above 100; instead, only 10 EVs are deducted.

Pokémon can now gain effort values from battling even at Level 100, and stats are recalculated at the end of every battle instead of only after leveling up, much like Deoxys in the Generation III games. When a Pokémon is defeated, EVs do not get added until after all experience points have been added (if the Pokémon levels up more than once, the second level it gains will have new EVs calculated into it). If a Pokémon levels up in the middle of a battle, its stats will update assuming there are EVs to add from a previously defeated opponent, but EVs from the opponent that caused it to level up will not be added until after the experience points have been completely added. This entire mechanic was overhauled in ; EVs are now added before Experience, so if the victorious Pokémon gains enough Experience to level up, its new stats when displayed in battle include the new EVs.

A new kind of item called Wings are introduced which are similar to Vitamins but only give 1 effort point when consumed. Unlike Vitamins however, Wings are not subject to the 100 EV limit and can be consumed until the maximum value of 255 for one stat (or a combined 510 for all stats) is reached. There are 7 types of Wings in total, but only 6 Wings contribute to a specific stat: the Pretty Wing does nothing at all. Wings can be collected from the shadows at the Driftveil Drawbridge or Marvelous Bridge and are given as prizes for clearing higher level floors in the Black Tower and White Treehollow.

In Pokémon Black 2 and White 2, Join Avenue's Beauty Salon, Dojo and Café can alter a Pokémon's EVs for a determined price.

Generation VI
All items and mechanics for effort values remain the same in Generation VI as they were in Generation V, except individual stats now max out at 252 EVs instead of 255. This provides no functional difference from previous generations, since stats are calculated by integer division of the effort values by 4, so having 252 EVs has the same effect on a stat as having 255.

Generation VI also introduced a new feature called Super Training, which allows the player to increase effort points for each stat individually, or remove all effort points from a Pokémon entirely. Super Training Regimens feature minigame activities where the Pokémon attacks various balloons with footballs/soccer balls, which award effort points for the stat of the player's choosing as well as awarding a Training Bag. Training Bags also typically increase effort points, though some of them have other effects—such as the Double-Up Bag, which doubles the number of effort points awarded after a Regimen, or the Reset Bag, which reduces all effort points on a single Pokémon to zero.

In Pokémon X and Y, EV-altering juices can be made or bought at the Juice Shoppe in Lumiose City. If the player mixes two Berries of the same color, they will produce an EV Juice that raises a stat corresponding to the Berries' color by an amount depending on the Berries used; pre-made EV Juices can also be purchased from the Juice Shoppe, with the available juices varying each day. If the player mixes a and Maranga Berry, they can produce the Perilous Soup, which reduces all effort points on a single Pokémon to zero.

Super Training exposes base stats to the player for the first time. Using a Reset Bag will numerically display the effort points a Pokémon just had, which can be reverted by restarting without saving. Additionally, high-level Pokémon can determine their individual values mathematically by inspecting the values of their stats after a Reset Bag is used.

Catching a wild Pokémon will now give EVs for that Pokémon as if it were defeated.

Generation VII
All mechanics for effort values remain the same in Generation VII as they were in Generation VI.

Pressing the Y button on the Summary screen of a Pokémon will now show an orange graph similar to that of Super Training, depicting how much EVs a Pokémon has accumulated so far. A maxed out stat will have sparkles around its name. When a Pokémon has 510 EVs in total, the graph will turn cyan.

The Macho Brace is unavailable in Pokémon Sun and Moon; however, the six Power Items introduced in Generation IV now yield an additional eight instead of four effort points per Pokémon defeated.

Although Super Training is no longer available, Pokémon Sun and Moon introduced Poké Pelago, which allows for passive EV-training of Pokémon currently stored in the PC. On, these Pokémon can be let out to play on one of three structures on the isle, with up to six Pokémon allowed per group. Each round lasts for thirty minutes, with a maximum of 99 per session allowed. The player can end play sessions early, and will keep all progress from hitherto completed rounds. Pokémon in play sessions cannot be accessed from the PC, but their Summaries can be checked while on Isle Evelup. During play sessions, special, purpose-made juices are given to the Pokémon, allowing for increases in effort points per stat. The effectiveness of these juices is determined by Isle Evelup's level.

Since the maximum EVs a Pokémon can get in any one stat is 252, it would take 63 sessions at Level 3 to max out one stat, for a total time of 31 hours and 30 minutes. This time can be cut in half by placing Poké Beans in the crate on the island.

Pokémon Sun and Moon also introduced SOS Battles. Most wild Pokémon can call an ally for help, turning a regular wild battle into an SOS Battle. All wild Pokémon summoned this way have their EV yields doubled upon being defeated. Thus, if a Pokémon holding a Power Weight and infected with Pokérus defeats a Caterpie, which gives 1 HP EV, it will earn 18 HP EVs; however, a Caterpie that is called as an ally will instead yield 36 HP EVs. In this way, only 7 ally Caterpie must be defeated to max out HP.

Similar to Pokémon Black 2 and White 2, Festival Plaza's Bouncy Houses and Food Stalls can alter a Pokémon's EVs for a predetermined price.

Fully Trained Pokémon
A Fully Trained Pokémon is a Pokémon that has reached 510 EVs overall, the maximum a Pokémon can achieve. In Generations III, IV, VI, and VII, there is an NPC that will give an to Fully Trained Pokémon; in Generation V, an NPC in Opelucid City will comment that the Pokémon has put in a lot of effort if it is a Fully Trained Pokémon.

In Pokémon X and Y and Pokémon Omega Ruby and Alpha Sapphire, Fully Trained Pokémon can access Secret Super-Training Regimens. Once a Pokémon has reached Fully Trained status, it will not lose it even if its EVs are removed, such as with a Reset Bag or.

In Pokémon Omega Ruby and Alpha Sapphire, Pathless Plain becomes accessible if the player has at least three Fully Trained Pokémon in his or her team.