No, not an IV of saline....
It’s time for another course in Pokemon Training! If you read Pokemon Training 102, then you got a quick briefing on what Individual Values (or IVs for short) are- but that hardly covers everything you’re going to want to know about them. That’s what this course is for.
Individual values are an inherent difference in a stat that exists in the pokemon game to ensure that each pokemon is different. The IVs are one of the two basic parts of a pokemon that keep, for instance, all Infernape from being equally good at physical and special offense to each other- and keep their physical and special attack stats, despite having the same base value, from always being equal to one another. Because Individual Values exist, some Infernapes will be better at physical offense, some will be better at special offense, and some will be evenly balanced. This difference- up to 31 stat points at level 100- initially seems fairly small- but keep in mind that even an offensive pokemon like an Infernape usually only has about two hundred and eighty points in their attack stats at level 100, IVs and EVs notwithstanding.
Because of this, it behooves you to actually look at the specific stats of your pokemon and determine what their IVs make them more suited before- before you start training in their EVs and choosing which moves the pokemon should learn.
Unfortunately, the IV modifier on a pokemon’s stat is only full at level 100. This means that it won’t usually be very apparent until the pokemon reaches level 10 or so, and to really discern what the difference is in detail requires raising a pokemon to level 50.
Calculators are available online that will let you plug in the pokemon’s BVs (Base Values) and determine the IVs the pokemon has, but these calculators have limits- and again these limits are discerned partly by the current level of the pokemon, being only really reliable after level 20 or so.
Of course, the IVs of a pokemon are inherent to the pokemon- and they can’t be changed. If you catch a Pikachu with a 0 IV in its Speed value, it’s always going to be slow for an electric mouse, no matter what you do. You can make up some of this difference with EVs, but that tends to be a matter of spending a resource you don’t have to spare.
IVs are the bane of many a trainer, because the only way to get different IVs is to get a new pokemon of that specie. This can mean lots of catching, or lots of breeding, in the search for the pokemon with the best stats for what you want it to do. Some people take this even further and will refuse to use a pokemon that doesn’t have maximum IVs in every stat. These people will either use cheats or spend ridiculous amounts of time just to make sure they squeeze every point of stat value they can out of their pokemon. Occasionally, you will get lucky and run across a pokemon (or hatch one) with ‘perfect’ IVs without spending a lot of time, but this tends to be a task of more difficulty and effort than catching a shiny pokemon of a species.