Pokemon Black Version 2

IV

These things are determined by individual pokemon itself hence individual value

It is a random value from 1 - 31 that determine how high a stats can become, that applied to every pokemon stats

These value are determined when the pokemon is generated, such as when you ecounter a pokemon, when you get an egg etc.

A "Perfect Pokemon" or "Flawless" is a term made for a pokemon for 31 IV in every stats

Trivia:
While "Flawless" pokemon are in a very high demand, in reality the only IV that you really need to have in 31 are speed. Optionally HP and an offensive stats as well.

At level 100, the stats difference caused by IV directly mirrors the IV difference.
Ex:

Neutral Nature 0 IV Attack Heracross will have 318 Attack
Neutral Nature 31 IV Attack Heracross will have 349 Attack

During Breeding 3 random IV from both parents would be inheritted by the child. However, note that you can control this a bit.

The Power(Anklet, Bracer, etc) items, when held to a parent will guarantee a 100% chance of an IV being inheritted depending on which power items you used. This inheritted IV count towards the 3 random IV from the parents

An easy way to check IV would be to use this:
http://www.psypokes.com/dex/iv.php

Before using that tool, go to PWT and enter a tourney with the pokemon you wanted to check. You can check up to 6 pokemon at once with the triple battle option. The reason PWT is used is because it has an autolevel to 50 feature. Note that you should keep an eye to your pokemon's EV as well
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