For most players, Pokémon games are a pretty straightforward affair of attacking enemies’ weaknesses and scoring that sweet one-shot. But Pokémon can become incredibly overwhelming once you start playing competitively. What’s an IV? What’s an EV, if not the cute brown fox who can evolve into a bunch of other, more colorful and elaborate foxes?

In fact, they refer to hidden numbers and background math that competitive players like to tweak and manipulate to create the strongest versions of their favorite ‘mons. EV and IVs stand for Effort Values and Individual Values. These hidden numbers determine the final state of a Pokémon’s six stats, and understanding how they work and how to influence them can give you an upper hand in competitive battling. Let’s take a closer look.

Not Eevee…EV!

Manipulating Effort Values is quite a time investment, as they’re entirely based on what you expose a Pokémon to as you raise them. Each Pokémon has up to 510 total EV points to distribute among all six stats, but each stat can only have 252 EVs individually.

You raise EVs by using items like vitamins and feathers, which each boost specific stats. Vitamins are the most immediately effective, as each will raise an individual stat by 10 EVs. Before Pokémon Sword and Shield, Vitamins were only effective up to a Pokémon’s first 100 EVs, but now, these items will work to max out an individual stat to the ceiling of 252. Feathers aren’t as powerful, raising an EV by only one point. Pretty straightforward so far, but influencing a Pokémon’s EVs while you train them in battle requires a little more planning.

Every Pokémon you battle grants specific EV boosts when defeated, often reflective of its own base stats. The amount of EVs you’ll get per stat depends on how powerful the Pokémon you’re fighting is. For example, if your Pokémon beats a Pichu, it will add one EV point added to your creature’s Speed stat. However, if you’re fighting its fully-evolved form Raichu, that will net you three Speed EV points. If you felt so compelled, you could go beat up a bunch of unsuspecting Pichu to raise a Pokémon’s Speed EVs, but you’ll hit the stat-specific 252 limit much faster if you’re battling more powerful Pokémon.

Some Pokémon don’t dump all their EVs into a single stat like Raichu does, however. Take Butterfree, for example. It divides its three EVs into Special Attack and Special Defense. So while there are better Pokémon to fight for either individual stat, defeating Pokémon who earn you a spread of EVs is a way to raise multiple EVs at once. It’s just a matter of your goals for stat raising and how you want to spend your time.

One thing worth noting about EVs is that, because modern Pokémon games allow an entire party to gain experience after battles, EVs gained are shared through your party as they gain experience, even if they’re not on the field. So be mindful of what you’re training against and what Pokémon you have waiting in the wings to join the fight, as their EVs will be influenced by these battles even if you’re not using them directly.

Grinding EV can take some time, but you can speed up the process of raising specific EV stats by equipping Pokémon with power items that correlate with a specific stat, such as the Power Anklet that increases Speed EVs, or the Power Belt that increases Defense EVs. All of these are purchasable at Delibird Presents stores for $10,000 each.

“The circumstances of one’s birth are irrelevant”

Individual Values, known as IV, are a bit more complicated. IVs are essentially Pokémon genetics, in that these are stat boosts inherent to the specific Pokémon you have, which range from zero points to 31 points. Once unchangeable, the Pokémon series has implemented various ways to influence them over the years.

Imagine you had two level 100 Raichus and one had 31 Speed IVs and the other had zero. Even if you trained these two Raichus exactly the same way and curated the same EV build, the one that was born with 31 Speed IVs would have a Speed stat 31 points higher than the other. A lot of competitive players will breed Pokémon to try and attain optimal IVs, as parent Pokémon pass on higher IVs based on their own to their offspring.

In more recent games, Pokémon has given players the ability to “Hyper Train” their ‘mons to increase their IVs in exchange for Bottle Caps. This can be done in locations like Montenevera in Scarlet and Violet by talking to a trainer standing close to the town’s Pokémon Center. Bottle Caps can be hard to come by. You can buy them at the Delibird Presents stores around Paldea, but they’re pretty pricey at $20,000 per cap. You can also win them in high-level tera raids, but often just as a random drop. So while it might seem more immediate to be able to use Hyper Training, acquiring those Bottle Caps can take time, which is why some players opt to max out a Ditto’s IVs and use it to breed better versions of whatever Pokémon they’re trying to raise.

“Just tell them that it’s Pokémon nature”

But no matter what a Pokémon’s EVs and IVs are, a few additional factors will determine whether or not it’s is inherently effective in certain builds compared to others.

Each Pokémon has a set of base stats inherent to its species that grow as you raise your critter, and the direction those numbers go will be determined by how its EVs and IVs pan out. Raichu’s base stats position it as a fast, special attack-driven Pokémon. It has a base speed stat of 110, and its special attack stat of 95 outshines its base physical attack, which is 85.

This helps you determine what attacks are probably most effective for it to learn. Its physical attack stat is still respectable, but at a glance, Raichu is meant to primarily be a special attacker. Understanding EVs and IVs can help you shift those scales, or at the very least make up for certain deficiencies. Raichu’s base physical defense stat is much lower than the rest, coming in at just 50, so if you wanted to help make up for that, raising its IVs through Hyper Training or fighting Pokémon that naturally raise physical defense EVs can help it bulk up a little. But those base stats can be influenced by another factor that can play into how you divvy up your EVs and IVs: Natures.

Alongside its universal base stats as a species, every individual Pokémon you come across will also come with a Nature. These appear in the status summary screens as a means to give you a sense of your Pokémon’s personality, but they also determine one increased stat and one decreased stat. As such, some players will breed multiple versions of a Pokémon in an effort to get one with the most desirable Nature and stat distribution for the build they want.

There are 25 total Natures in Pokémon games right now, and the stats they increase and decrease are as follows, courtesy of Serebii:

Hardy: No change
Lonely: Attack/Defense
Brave: Attack/Speed
Adamant: Attack/Special Attack
Naughty: Attack/Special Defense
Bold: Defense/Attack
Docile: No change
Relaxed: Defense/Speed
Impish: Defense/Speed
Lax: Defense/Special Defense
Timid: Speed/Attack
Hasty: Speed/Defense
Serious: No change
Jolly: Speed/Special Attack
Naive: Speed/Special Defense
Modest: Special Attack/Attack
Mild: Special Attack/Defense
Quiet: Special Attack/Speed
Bashful: No Change
Rash: Special Attack/Special Defense
Calm: Special Defense/Attack
Gentle: Special Defense/Defense
Sassy: Special Defense/Speed
Careful: Special Defense/Special Attack
Quirky: No Change

While Natures themselves are fixed, Sword and Shield introduced Mints, a new set of items that can change the stat distribution associated with them. For example, a Modest Mint will increase a Pokémon’s Special Attack, but reduce the Attack stat as if the Pokémon’s Nature had changed. This won’t change the actual personality it talks about in their summary (that would be brainwashing), but it will allow you to tweak their stats for any competitive schemes you might have in mind.

Different pokés for different folks

All of these moving parts can be a lot to keep track of, and these mechanics are really there for the sickest of competitive sickos. It can be rewarding to get a Pokémon to the competitive state you want and see them excel in battles, but it’s also a huge time investment to get your team’s numbers precisely dialed in. But if you’re curious about the world of competitive Pokémon, understanding EVs and IVs is a good metric for whether or not this side of the scene is for you. And if it’s not, you can still do cool tera raids with your friends, like the ongoing Charizard one happening in Scarlet and Violet right now.