Here's a guide on specifically IV breeding. Though they are mentioned, I don't explain EV's and natures in this guide.
Breeding for natures however will clash somewhat with the information in this guide, so if you want to breed for both nature and IV's, don't start on this information alone, read my nature breeding guide if you want to learn how to breed natures.
If you're not a patient person, this method requires patience, and you may want to stick with just EV training. EV training can potentially do significantly more increase in stats in a single stat than IV's, and does not take too long to do. However, though EV training will make your pokemon significantly stronger on its own, those who do IV train also will have a pretty good edge on you.
If you want, you can leave questions, comments, concerns, complaints, or even compliments
criticism would be good too.
Explanation of IV’s:
IV's are random numbers from 0-31, each of your pokemon stats have one of these randoms numbers, and those are the IV's. The number means how many additional stat points that stat will have overall, when it reaches level 100. So lets say a pikachu with 0 IV's in speed will have 200 speed at level 100, but a pikachu with 31 IV's in speed, will have 231 speed at level 100.
However, you do have some control over what IV's your pokemon have, but you can only do this through breeding. When you breed a pokemon from the daycare center, all of its IV are randomly set initially, then one random IV from either of the parents is inherited and overwrites the initial IV of that stat. . Then a second IV that is not an HP IV, is randomly inherited from either of the parents. Then a third IV that is not an HP or a Defense IV is randomly inherited from either of the parents. So a total 3 IV's are inherited from the parents, however, HP and Defense IV's have less of a chance of being passed down. These IV's may overlap, so the same kind of IV could be selected more than once and overwrite the previously selected IV.
You can find out how many IV’s your pokemon have in each stat by using several online calculators that are available online. They require you to know how many EV’s your pokemon have in each stat, so make sure you know that. Pokemon you just caught, hatched, or only leveled up by rare candies or day care will not have any EV’s.
In terms of accuracy, Metal Kid's calculator is the best IV calculator out there. Click here.
Example of IV breeding:
Parent 1 IV: 31/30/29/28/27/26
Parent 2 IV: 25/24/23/22/21/20
Offspring IV: 19/18/17/16/15/14
So in the first round of inheritance, lets say the offsrping inherits parent 1's HP IV, so now the offsprings IV's are...
In the second round of inheritance, it can't inherit HP IV's from the parents, so lets say it gained the speed IV of parent 2...
In the third and last round of inheritance, it can't inherit HP or defense IV's, so lets say it gained the sp. def IV of parent 2...
So these are now the IV's of the offspring.
Tips on Breeding for IV’s:
When people try to breed for IV’s, they usually only care about 2 or 3 stats that they think are most important. If you want to breed an Alakazam for example, most people would only care about good IV’s in its Sp. Attack and Speed stats.
This is because it can take an extremely long time to breed for good IV’s in all, or nearly all of its stats. Remember that even if the parent pokemon have good IV’s in all of its stats, only 3 are randomly inherited by the offspring and the rest of its stats are random. Although, having the parents have good IV’s in all the stats you care about will give the offspring a better chance of getting good IV’s in those stats as well.
What's considered "good" or "acceptable" IV's is completely up to you. I personally would breed till all IV's I care about are above 20. But it's completely your choice on what you would consider "acceptable" IV's.
What I suggest you do when breeding for IV’s is to first choose what stats you want good IV’s in. Then find out the IV’s of the parents. Know the number of acceptable IV’s each parent has in those stats you care about. Then start breeding with those parents. When you start getting offspring, check their IV’s. NOTE: The calculators you use to find IV’s are more precise at higher levels, so its best to save the game give it some rare candies or leave it at the day care, I’d say to around level 15, check the IV’s, and then reset.
If there are more good IV’s in the stats you care about in the offspring than in its parent of the same gender, then you should replace the parent with the offspring. If the offspring have a less amount of good IV’s or the same amount of good IV’s as its parent with the same gender, then you should just release it. Making the parents have more good IV’s in the stats you care about will make the offspring have a better chance of getting good IV’s in all of the stats you care about. You should keep doing this until you finally breed the pokemon with good IV’s in all the stats you care about.
Having a pokemon with magma armor or lava body ability in your party will reduce the amount of steps needed to hatch eggs.
Breeding non-gender pokemon:
If you read the guide, you pretty much know almost everything you need to know on specifically IV breeding. However, there is one situation that makes things just a tad little more complicated. That is trying to IV breed pokemon that don’t have a gender.
Pokemon with no gender can only breed with ditto and that’s it, not even a pokemon of the same species. So a Metagross can breed with a ditto, but not with another Metagross. Also, dittos can’t breed with other dittos, only with other pokemon.
So, if you want to IV breed a ditto, it’s impossible, can’t happen, forget it. But you can still IV breed other non-gender pokemon. What you should do to IV breed that other pokemon is to keep catching dittos until you find one with good IV’s in all the stats you care about. Then you can start breeding with that other non-gender pokemon.
Check the IV’s of the offspring, replace the parent if the offspring has more good IV’s than the parent, release if not. Then continue until you finally breed the one with good IV’s in all the stats you care about.
When you look at the summary of your pokemon and look at the trainer memo page, the page where it shows the nature and such. The second comment from the bottom, the one above what kind of food it likes, tells what may appear to be a random comment like "mischievous" or "somewhat of a clown." These descriptions however actually identify an IV that your pokemon has. Here is a list of what the descriptions can mean. Notice that each description could have several possible IV values of a certain stat, so it's easy to think that by having a characteristic of "Often Dozes Off" you may believe you have 31 IV's when it's just as possible you actually only have 1 IV. I'll up date this part if I find a more useful way to use IV characteristics.
0 5 10 15 20 25 30 Loves To Eat
1 6 11 16 21 26 31 Often Dozes Off
2 7 12 17 22 27 Often Naps
3 8 13 18 23 28 Often Scatters Things
4 9 14 19 24 29 Likes To Relax
0 5 10 15 20 25 30 Proud Of Its Power
1 6 11 16 21 26 31 Likes To Thrash About
2 7 12 17 22 27 A Little Quick Tempered
3 8 13 18 23 28 Likes To Fight
4 9 14 19 24 29 Hot Tempered
0 5 10 15 20 25 30 Sturdy Body
1 6 11 16 21 26 31 Capable Of Taking Hits
2 7 12 17 22 27 Highly Persistent
3 8 13 18 23 28 Good Endurance
4 9 14 19 24 29 Good Perseverance
0 5 10 15 20 25 30 Highly Curious
1 6 11 16 21 26 31 Mischievous
2 7 12 17 22 27 Thoroughly Cunning
3 8 13 18 23 28 Often Lost In Thought
4 9 14 19 24 29 Very Finicky
0 5 10 15 20 25 30 Strong Willed
1 6 11 16 21 26 31 Somewhat Vain
2 7 12 17 22 27 Strongly Defiant
3 8 13 18 23 28 Hates To Lose
4 9 14 19 24 29 Somewhat Stubborn
0 5 10 15 20 25 30 Likes To Run
1 6 11 16 21 26 31 Alert To Sounds
2 7 12 17 22 27 Impetuous And Silly
3 8 13 18 23 28 Somewhat Of A Clown
4 9 14 19 24 29 Quick To Flee
Don't copy and paste this guide anywhere! But you can still link if you want.
Read my nature breeding guide to learn how to breed natures and then read the breeding for both IV's and Nature guide to make a very strong pokemon