Helpful Guide to Individual Values and Effort Values
Individual Values or IVs are hidden numbers that are added to each stat: Hit Points (HP), Attack, Defense, Special Attack, Special Defense and Speed. These numbers range from 0-31 for each stat and will gradually add to that particular stat until the pokémon reaches level 100.
For instance if a pokémon has a 24 IV in a particular stat, at level 25, it will be 6 stat points higher than its base stat solely due to its IV. At level 50, it will be 12 points above its base stat. At level 75, it will be 18 points above its base stat and at level 100 you will find all 24 points will show up in its stat
Although these numbers are hidden, the effects on each stat are not. By charting the increase in stat values you can determine what these IVs are by use of a complicated mathematical equation or by using an IV calculator.
Effort Values or EVs are gradually added to each stat as a reward for pokémon battling experience. Each pokémon you battle either in the wild or by battling a trainer or Gym leader in the game has an assigned Effort Value. Unlike experience points that are divided among all the pokémon in the battle and those with Experience Share, all the pokémon involved receive full share in EVs.
These Effort Values range in each stat from 0-255. The maximum total Effort Values counted towards each pokémon is 510 for all stats combined. For every 4 EVs in one particular stat, 1 point is added to that stat. Since you need 4 EVs to add one stat point, the maximum EVs that can be used is 252 for each stat equal to 63 stat points. Similar to IVs these will be distributed as the pokemon grows in level until it reaches level 100.
Changes in IV breeding in Gen VI
Unlike previous generations where the Hp and Defense IVs were filled first, all IVs have an equal chance of passing down to the offspring. Three IVs are always passed down and without the use of power items the odds of passing IVs to offspring are:
25% chance of inheriting 3 of Parent A's IVs and 0 of Parent B's IVs.
25% chance of inheriting 2 of Parent A's IVs and 1 of Parent B's IVs.
25% chance of inheriting 1 of Parent A's IVs and 2 of Parent B's IVs.
25% chance of inheriting 0 of Parent A's IVs and 3 of Parent B's IVs.
Of course a power item will assure at least one of that parents IV being passed down.
With half of the IVs coming from the parents it is more than ever important to have parents with superior IVs.
Destiny Knot has a new breeding quality now. If one of the parents are holding it while breeding, five IVs will be passed down instead of three. These are picked at random between the parents. All five may come from one parent.
Breeding two parents with 6 perfect IVs will produce offspring with at least 5 IVs and a 1 in 32 chance of a perfect offspring.
Breeding two parents with the same 5 IVs has a 19.75% chance of producing offspring with those same IVs.