PART I
Introduction to Breeding
Other parts of the guide:
Part II: The Breeding guide
Part III: Emerald, Diamond and Pearl IV breeding combinations probabilities list
Part IV: Hidden power breeding
Table of content, Part I:
Section One: Introduction to IVs and Nature
Section Two: How to discover the IVs of your Pokémon
1. Estimation
2. The Battle Frontier IV guy
3. IV calculator
4. Wi-Fi IV battles
Section Three: How IVs are passed to the baby
1. Emerald, Diamond and Pearl
2. Ruby, Sapphire, Fire Red, Leaf Green
3. Probabilities for IV breeding
Credits
SECTION ONE
Introduction to IVs and Nature
Individual Values, or IVs for short (sometimes also called Diversification Values or DVs) are essentially numbers that act as the Pokémon's "genes". Every Pokémon has a "gene" for each of its stats (HP, Attack, Defense, Special Attack, Special Defense and Speed), which is a number between 0 and 31. The higher the number, the better that particular stat will be for that Pokémon. The player cannot alter the IVs of any Pokémon in any way. They are set in stone the moment you encounter that Pokémon in the wild, or the moment that Pokémon’s egg is given to you.
Since the player cannot change the IVs of his or her Pokémon, the temptation would be not to even bother about IVs. However, IVs are very important, since a good IV may add up to 31 to a particular stat when the Pokémon is at Level 100, and sometimes even more than that, if that stat is being boosted by a favourable nature (see the next paragraph). It also turns out that, while breeding, some IVs of the parents are actually passed to the baby, and so, if the parents already have a few good, or even perfect IVs (31), then the baby would have a chance of inheriting them. Thus, breeding for perfect IVs is not only important, but also possible without cheating, and that is the whole scope of this guide.
In addition, each Pokémon has a nature (sometimes also called personality). Most of these natures modify that Pokémon's stats in some way. There are 25 possible natures. Here is a list of them and what each does to your Pokémon.
Natures that boost Attack
Lonely: Increases your Attack stat by 10%, and decreases your Defense stat by 10%.
Adamant: Increases your Attack stat by 10%, and decreases your Special Attack stat by 10%.
Naughty: Increases your Attack stat by 10%, and decreases your Special Defense stat by 10%.
Brave: Increases your Attack stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Defense
Bold: Increases your Defense stat by 10%, and decreases your Attack stat by 10%.
Impish: Increases your Defense stat by 10%, and decreases your Special Attack stat by 10%.
Lax: Increases your Defense stat by 10%, and decreases your Special Defense stat by 10%.
Relaxed: Increases your Defense stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Special Attack
Modest: Increases your Special Attack stat by 10%, and decreases your Attack stat by 10%.
Mild: Increases your Special Attack stat by 10%, and decreases your Defense stat by 10%.
Rash: Increases your Special Attack stat by 10%, and decreases your Special Defense stat by 10%.
Quiet: Increases your Special Attack stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Special Defense
Calm: Increases your Special Defense stat by 10%, and decreases your Attack stat by 10%.
Gentle: Increases your Special Defense stat by 10%, and decreases your Defense stat by 10%.
Careful: Increases your Special Defense Stat by 10%, and decreases your Special Attack stat by 10%.
Sassy: Increases your Special Defense stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Speed
Timid: Increases your Speed stat by 10%, and decreases your Attack stat by 10%.
Hasty: Increases your Speed stat by 10%, and decreases your Defense stat by 10%.
Jolly: Increases your Speed stat by 10%, and decreases your Special Attack stat by 10%.
Naive: Increases your Speed stat by 10%, and decreases your Special Defense stat by 10%.
Neutral natures
Hardy: No effect.
Bashful: No effect.
Docile: No effect.
Quirky: No effect.
Serious: No effect.
If you want your Pokémon to have the highest speed possible, for example, you'll want it to have a 31 Speed IV and a nature that boosts Speed. This guide will also show you how to breed such a Pokémon.
Abbreviations Explained
If you find a group of letters, or one letter, it means that what follows works only for the games referred by those letters. The letters stand for the following:
R - Pokémon Ruby
S - Pokémon Sapphire
FR - Pokémon Fire Red
LG - Pokémon Leaf Green
E - Pokémon Emerald
D - Pokémon Diamond
P - Pokémon Pearl
SECTION TWO
How to discover the IVs of your Pokémon
You might think that the IVs of a Pokémon can be found rather easily among that particular Pokémon's stats. The truth is, the game conceals the IVs of your Pokémon, and rather well at that. So how can we discover the IVs of our Pokémon?
1. Estimation
When you breed a Pokémon and the egg hatches, the Pokémon will hatch at Level 5. (In DP, it hatches at Level 1. To make it Level 5, give it 4 Rare Candies.) Even at this low level, you can have a rough estimate of your IVs by looking at the babies’ stats if you know the base stats of that Pokémon.
At Level 5, if a particular stat is unaffected by the Pokémon's nature, that stat always has the following minimum and maximum numbers:
Minimum Stat = a + 5
Maximum Stat = a + 6, if b is between 0 and 4
Maximum Stat = a + 7, if b is between 5 and 9
where a is the base stat with the last digit removed and b is the last digit of the base stat. Moreover, if the stat is HP, add 10 to both the minimum and maximum stats.
If the stat is boosted by the Pokémon's nature and the stats above has more than one digit, add the first digit of that stat to it. For example, if the minimum stat calculated above is 8, then it stays 8. If, however, it is 16, add 1 (the first digit of 16) to 16, becoming 17.
If the stat is hindered by the Pokémon’s nature, first subtract the stat by 1. Then, if that resulting number has more than one digit, subtract it further by the first digit of that stat. For example, if the maximum stat calculated above is 10, then subtract 1 from it, becoming 9. Since 9 is a one-digit number, it stays 9. If, in another example, the maximum stat calculated above was 13, then subtract 1 from it, becoming 12. Since 12 is a two-digit number, we subtract it further by 1 (the first digit of 12), becoming 11.
Also, if your Pokémon has a maximum stat at Level 5, then:
If b is between 0 and 4, the IV for that stat is between 20 – 2b and 31.
If b is between 5 and 9, the IV for that stat is between 40 - 2b and 31.
The above information can be used to see roughly if the Pokémon’s IVs are bad, so that you can release it immediately if they are not good enough before proceeding to find the IVs more exactly.
Let's give an example. Suppose you have bred a Magikarp, and want to check if your Speed stat has a good IV or not. Let's assume that your Magikarp has a Jolly nature.
Magikarp's base Speed stat is 80. In our case, a = 8 and b = 0. So the minimum speed stat is 8 + 5 = 13. Since the stat is boosted by Jolly, we add 1 (first digit of 13) to 13, becoming 14. The maximum speed stat is 8 + 6 = 14. Again, since the stat is boosted by Jolly, we add 1 (first digit of 14) to 14, becoming 15. So, if the Magikarp's speed stat is 14, you can dismiss that Magikarp out of hand.
If the Magikarp has a maximum Speed stat of 15, then its IVs are in the range 20 - 2(0) and 31, i.e. between 20 and 31.
Let's give another example. Suppose you breed a Timid Treecko and you want it to have a high Special Attack stat. Treecko's base Special Attack is 65, so a = 6 and b = 5.
Its minimum special attack stat at level 5 is thus 6 + 5 = 11. Its maximum special attack stat is 6 + 7 = 13.
If your newborn Treecko has a special attack stat 11 or 12, then you dismiss it. If it has a Special Attack stat of 13, it means that its Special Attack IV is between 40-2(5) and 31; i.e. between 30 and 31 - a very good IV indeed.
The maximum stats of all the bred Pokémon at Level 5 can also be found in Part II, Section 5 of this breeding guide, for a quicker reference.
2. The Battle Frontier IV guy (only in E)
In Emerald, you can check your IVs by speaking to a man who lives in a house just above the Pokémon Center of the Battle Frontier. He will give you an overall judgment of all the IVs and the best IV of one of your Pokémon.
He will say the following:
“Ah, youngster! Do your Pokémon's abilities intrigue you? Here, here! Let's have a look at your Pokémon!”
You then choose the Pokémon that you need its IVs checked. He will then say:
"...Hmm...This one, overall, ..."
and then one of the following four:
"I would describe as being of average ability. "
-> the total of the six IVs is a number between 0 and 90 (average IV is between 0 and 15)
"I would describe as having better-than-average ability. "
-> the total of the six IVs is a number between 91 and 120 (average IV is greater than 15 but less than or equal to 20)
"I would say is quite impressive in ability!"
-> the total of the six IVs is a number between 121 and 150 (average IV is greater than 20 but less than or equal to 25)
"I would say is wonderfully outstanding in ability!"
-> the total of the six IVs is a number between 151 and 186 (average IV is greater than 25)
Then the man will proceed to mention the best IV that Pokémon possesses. If it has more than one best IV, this will be random. Talking to the man repeatedly will make him speak about the other equally best stats.
"Incidentally, the best aspect of it, I would say, is its (HP / ATTACK / DEFENSE / SPECIAL ATTACK / SPECIAL DEFENSE / SPEED) ..."
He then gives a judgment about that IV alone:
If the IV is between 0 and 15, the man will say: "That stat is relatively good."
If the IV is between 16 and 25, the man will say: "That stat is quite impressive."
If the IV is between 26 and 30, the man will say: "That stat is outstanding!"
If the IV is 31, the man will say: "It's flawless! A thing of perfection!"
The man will then finish up his monologue with the words: "...Hm... That's how I call it."
This Emerald feature is very handy to check if your Pokémon has a perfect IV.
3. IV calculator
If you prefer to just enter your stats in an IV calculator for it to work out the IVs for you, there are a few online programs that do just that. The best one is perhaps MetalKid's IV calculator, which can be found here. You input the stats of your Pokémon as you level it up with a few Rare Candies, and the program finds the IVs of your Pokémon for you. Refer to the actual site for more information.
4. Wi-Fi IV battles (DP only)
In DP only, if you battle against someone using the Wi-Fi connection, you can select an option to scale your battling Pokemon to Level 100. When this option is chosen, their stats are automatically calculated for Level 100, even though the Pokémon itself may not be a Level 100 one. This feature allows you to find the exact IVs of up to six of your Pokémon that have not yet battled, because, at Level 100, the IVs of the Pokémon can be calculated exactly in the vast majority of cases.
First, find a friend who is willing to let you check the IVs of all your Pokémon. (He or she might also want to do the same thing with his or her Pokémon.) Connect with him for a battle, and write down the stats of your Pokémon. When you’re ready, you and your friend simply run from the battle, and the battle ends.
The IVs can then be calculated as follows:
If the stat is hindered by the Pokémon’s nature:
IV = ceil(Stat * 10 / 9) – (2 * Base + Num) if Stat is not divisible by 9. If Stat is divisible by 9, then, unfortunately, the IV can be one of two numbers: either the one calculated here, or 1 more than that.
If the stat is boosted by the Pokémon’s nature:
IV = ceil(Stat * 10 / 11) – (2 * Base + Num)
If the stat is unaffected by the Pokémon’s nature:
IV = Stat – (2 * Base + Num)
where
ceil(x) is x rounded up. For example, ceil(5.6) = 6, ceil(18.01) = 19, and ceil(7) = 7.
Stat is the Pokémon’s stat at Level 100
Base is the base stat
Num is 110 if the stat is HP, and 5 otherwise.
For example, suppose you have just bred a Modest Chimchar which hasn’t battled yet, and you want to know its IVs. Let’s say that the stats that were noted during the Wi-Fi battle were the following:
HP: 210
Attack: 127
Defense: 97
Special Attack: 167
Special Defense: 102
Speed: 153
Chimchar’s Base Stats are:
HP: 44
Attack: 58
Defense: 44
Special Attack: 58
Special Defense: 44
Speed: 61
The HP IV is 210 – (2 * 44 + 110) = 210 – 198 = 12.
The Attack IV is ceil(127 * 10 / 9) – (2 * 58 + 5) = ceil(141.111) – 121 = 142 – 121 = 21. (Since 127 is not divisible by 9, this IV is exact.)
The Defense IV is 97 – (2 * 44 + 5) = 97 – 93 = 4.
The Special Attack IV is ceil(167 * 10 / 11) – (2 * 58 + 5) = ceil(151.818 ) – 121 = 152 – 121 = 31.
The Special Defense IV is 102 – (2 * 44 + 5) = 102 – 93 = 9.
The Speed IV = 153 – (2 * 61 + 5) = 153 – 127 = 26.
Of course, if you´re not able to calculate or simply don´t want to calculate the IVs this way, you can use Metalkid´s IV calculator (see above) to get your results.
5. Pokemon Characteristics (DP only)
This method does not provide the player with all of the Pokemon's IVs, but it does shed a very accurate light on the value of the highest IV of the Pokemon at a glance, which is very useful when breeding for 31 IVs in a particular stat. It is also useful when mass catching Ditto in DP since it provides a quick way of knowing if a Pokemon's highest IV is not 31.
DP introduced Pokemon characteristics, which is a short phrase that gives an idea on which is the stat with the highest IV of that Pokemon, as well as a rough idea of how high it is. The following is a list of all the Pokemon characteristics:
If the Pokemon's highest IV is in the HP stat:
Loves to eat - The HP IV's last digit is 0 or 5.
Often dozes off - The HP IV's last digit is 1 or 6.
Often scatters things - The HP IV's last digit is 2 or 7.
Scatters things often - The HP IV's last digit is 3 or 8.
Likes to relax - The HP IV's last dight is 4 or 9.
If the Pokemon's highest IV is in the Attack stat:
Proud of its power - The Attack IV's last digit is 0 or 5.
Likes to thrash about - The Attack IV's last digit is 1 or 6.
A little quick tempered - The Attack IV's last digit is 2 or 7.
Likes to fight - The Attack IV's last digit is 3 or 8.
Quick tempered - The Attack IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Defense stat:
Sturdy body - The Defense IV's last digit is 0 or 5.
Capable of taking hits - The Defense IV's last digit is 1 or 6.
Highly persistent - The Defense IV's last digit is 2 or 7.
Good endurance - The Defense IV's last digit is 3 or 8.
Good perseverance - The Defense IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Special Attack stat:
Highly curious - The Special Attack IV's last digit is 0 or 5.
Mischievous - The Special Attack IV's last digit is 1 or 6.
Thouroughly cunning - The Special Attack IV's last digit is 2 or 7.
Often lost in thought - The Special Attack IV's last digit is 3 or 8.
Very finicky - The Special Attack IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Special Defense stat:
Strong willed - The Special Defense IV's last digit is 0 or 5.
Somewhat vain - The Special Defense IV's last digit is 1 or 6.
Strongly defiant - The Special Defense IV's last digit is 2 or 7.
Hates to lose - The Special Defense IV's last digit is 3 or 8.
Somewhat stubborn - The Special Defense IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Speed stat:
Likes to run - The Speed IV's last digit is 0 or 5.
Alert to sounds - The Speed IV's last digit is 1 or 6.
Impetuous and silly - The Speed IV's last digit is 2 or 7.
Somewhat of a clown - The Speed IV's last digit is 3 or 8.
Quick to flee - The Speed IV's last digit is 4 or 9.
So if a Pokemon's IVs, for example, are 20, 13, 6, 19, 25 and 19 (in the order HP, Attack, Defense, Special Attack, Special Defense and Speed), then its characteristic would be "Strong willed" (the highest IV is in the Special Defense stat and its last digit is 5). If there are two or more equal highest IVs, the characteristic for that Pokemon will be for one of those stats at random. So, if, for example, another Pokemon's IVs are 24, 31, 17, 8, 0 and 31, then the Pokemon's characteristic will either be "Likes to thrash about" or "Alert to sounds".
As you can see, if the characteristic of a Pokemon is not one of the 6 marked in bold, then that Pokemon is sure not to have a 31 IV in any of the stats, and can be immediately released while breeding. Of course, if it is one of the bolded six characteristics, you still need to check that it is indeed 31, but the value of the stat itself after the Pokemon is given a few Rare Candies usually tells you immediately whether it is 31 or not.
This makes it much easier to check for 31 IVs in stats, which is a very important shortcut when breeding in DP. Unfortunately, the Pokemon characteristics are of little use to calculate the remaining 5 IVs of the Pokemon, so you'll still need to use one of the previously mentioned methods to discover them.
SECTION THREE
How the game provides IVs to an egg
Before we start our breeding guide, you need to be informed of how exactly the game assigns the IVs to a baby. This actually differs from game to game.
1. IV Breeding in EDP
The IVs for the baby are first created at random. Then, a random IV from either parent is inherited to the baby. Then, any random IV except an HP IV is selected from either parent and is passed to the baby. Finally, any random IV except an HP or Defense IV is selected from either parent and passed to the baby. These three random IVs may overlap, that is, the same random IV can be chosen to be inherited in the second, or third, IV transfer.
Let's give an example:
Parent A has the following IVs: 21, 7, 26, 15, 4, 10.
Parent B has the following IVs: 5, 3, 16, 30, 28, 20.
(These, and all IV sets that will be listed, are written in the following order: HP IV, Attack IV, Defense IV, Special Attack IV, Special Defense IV, and Speed IV.)
First, the baby's IVs are generated at random: 18, 0, 9, 14, 11, 27.
Then a parent's random IV is chosen, and passed to the baby. Suppose Parent A's Speed IV is chosen first. So now the baby's IVs are: 18, 0, 9, 14, 11, 10.
Then a parent's random IV (other than an HP IV) is chosen, and passed to the baby. Suppose Parent A's Defense IV is chosen.
So now the baby's IVs are: 18, 0, 26, 14, 11, 10.
Finally, a parent's random IV (other than an HP or a Defense IV) is chosen, and inherited to the baby. Suppose Parent B's Special Attack IV is chosen. And the baby's IVs thus become: 18, 0, 26, 30, 11, 10.
Note that the amount of IVs passed from the parents is not always 3, for the following two reasons. Firstly, the random baby IVs created at the start might match some of the IVs of the parents, which would seem as if the baby got passed more than 3 IVs. Secondly, two or three of the IVs passed to the baby might be in the same stat, which would seem as if the baby got passed less than 3 IVs.
This means that the baby will always inherit between 1 and 6 IVs from the parents. The chances are as follows:
1 IV: 2.44% chance
2 IVs: 34.41% chance
3 IVs: 53.01% chance
4 IVs: 9.55% chance
5 IVs: 0.58% chance
6 IVs: 0.01% chance
The majority of eggs (about 8 out of 9 eggs) will have 2 or 3 IVs transferred from the parents.
HP and Defense IVs are harder to inherit from the parents than the other IVs. This is different from the other games (see RSFRLG IV breeding), where each IV has the same percentage of being transferred to the baby (16.67%). The percentages for Emerald (and DP) are as follows (considering also the fact that the random IVs generated for the baby can end up to be the same as that of one of the parent's IVs):
HP: 8.02% chance of being inherited
Atk: 19.55% chance of being inherited
Def: 13.78% chance of being inherited
SpAtk: 19.55% chance of being inherited
SpDef: 19.55% chance of being inherited
Speed: 19.55% chance of being inherited
This means that in EDP, the Attack, Speed, Special Attack and Special Defense IVs have a better probability of being passed to the baby than in RSFRLG, while the HP and Defense IVs have a worse probability of being passed to the baby than in RSFRLG.
SUMMARY: Emerald, Diamond and Pearl
1. The baby’s IVs are created at random.
2. Then a random IV is passed from one of the parents to the baby. The previous IV is overwritten.
3. Another random IV from Attack, Defense, Special Attack, Special Defense and Speed is passed from one of the parents to the baby. The previous IV is overwritten.
4. Finally, another random IV from Attack, Special Attack, Special Defense and Speed is passed from one of the parents to the baby. The previous IV is overwritten.
2. IV Breeding in RSFRLG
The IVs for the baby are first created at random. Then, three random IVs from either parent are successively inherited to the baby. These three random IVs may not overlap, that is, the same random IV cannot be chosen to be inherited in the second, or third, IV transfer.
Let's give an example to make things clearer. Suppose the parents have the same IVs as before. Let's recapitulate:
The first parent (Parent A) has the following IVs: 21, 7, 26, 15, 4, 10.
The second parent (Parent B) has the following IVs: 5, 3, 16, 30, 28, 20.
First, the baby's IVs are generated at random: 18, 0, 9, 14, 11, 27.
Then a parent's random IV is chosen, and passed to the baby. This is repeated three times.
Suppose Parent A's Speed IV is chosen first. So now the baby's IVs are: 18, 0, 9, 14, 11, 10.
Then Parent A's HP IV is chosen. So now the baby's IVs are: 5, 0, 9, 14, 11, 10.
Finally, Parent B's Defense IV is chosen. And the baby's IVs thus become: 5, 0, 16, 14, 11, 10.
Note that the amount of IVs passed from the parents is, again, not always 3, but this time, there will always be at least 3 IVs that are passed to the baby. As before, though, the random baby IVs created at the start might match some of the IVs of the parents, which would seem as if the baby got passed more than 3 IVs. The chances for each of them happening are these:
3 IVs: 82.66% chance
4 IVs: 16.26% chance
5 IVs: 1.06% chance
6 IVs: 0.02% chance
SUMMARY: Ruby, Sapphire, Fire Red, Leaf Green
1. The game first creates the IVs of the baby at random
2. Then it overwrites three of the parents’ IVs to the baby, one after the other. These three parents IVs never overlap.
3. Probabilities for IV Breeding
Now, I think you're asking "What is the probability, given two parents with a few perfect IVs (31) in certain stats, for the baby to obtain those same perfect IVs in those stats?" To answer that question, the following applet was created, which can be accessed here.
You input the parent's IVs (you have only two choices for each IV: either it's between 0 and 30, or 31). Then click on whichever IVs you want the baby to be 31. Choose whether the game is RSFRLG (Ruby/Sapphire) or EDP (Emerald), and the applet will find the probability that the baby will have those 31 IVs, together with the amount of eggs you are expected to hatch in order to have such a baby. For example, in Emerald (and Diamond/Pearl), if both parents have a 31 HP IV, the baby has a 19.27% chance of getting a 31 IV in HP, according to the applet. For Ruby/Sapphire (and Fire Red/Leaf Green), the probability is much higher, at 51.56%.
Later on, in Part III of this guide (see link at the start of this part), a list of all the breeding combinations with their probabilities of inheriting IVs will be given. There, you can simply compare various methods of getting the desired IVs and save as much time as possible in the breeding process.
Credits
We would like to thank:
1) BobDoily for providing the IVs of many test eggs, which helped in the discovery of how the IVs of the eggs are generated.
2) loadingNOW for finding out how the game provides IVs to the egg by looking at the Ruby and Emerald ROMs.
3) MetalKid for his great IV calculator.
Introduction to Breeding
Other parts of the guide:
Part II: The Breeding guide
Part III: Emerald, Diamond and Pearl IV breeding combinations probabilities list
Part IV: Hidden power breeding
Table of content, Part I:
Section One: Introduction to IVs and Nature
Section Two: How to discover the IVs of your Pokémon
1. Estimation
2. The Battle Frontier IV guy
3. IV calculator
4. Wi-Fi IV battles
Section Three: How IVs are passed to the baby
1. Emerald, Diamond and Pearl
2. Ruby, Sapphire, Fire Red, Leaf Green
3. Probabilities for IV breeding
Credits
SECTION ONE
Introduction to IVs and Nature
Individual Values, or IVs for short (sometimes also called Diversification Values or DVs) are essentially numbers that act as the Pokémon's "genes". Every Pokémon has a "gene" for each of its stats (HP, Attack, Defense, Special Attack, Special Defense and Speed), which is a number between 0 and 31. The higher the number, the better that particular stat will be for that Pokémon. The player cannot alter the IVs of any Pokémon in any way. They are set in stone the moment you encounter that Pokémon in the wild, or the moment that Pokémon’s egg is given to you.
Since the player cannot change the IVs of his or her Pokémon, the temptation would be not to even bother about IVs. However, IVs are very important, since a good IV may add up to 31 to a particular stat when the Pokémon is at Level 100, and sometimes even more than that, if that stat is being boosted by a favourable nature (see the next paragraph). It also turns out that, while breeding, some IVs of the parents are actually passed to the baby, and so, if the parents already have a few good, or even perfect IVs (31), then the baby would have a chance of inheriting them. Thus, breeding for perfect IVs is not only important, but also possible without cheating, and that is the whole scope of this guide.
In addition, each Pokémon has a nature (sometimes also called personality). Most of these natures modify that Pokémon's stats in some way. There are 25 possible natures. Here is a list of them and what each does to your Pokémon.
Natures that boost Attack
Lonely: Increases your Attack stat by 10%, and decreases your Defense stat by 10%.
Adamant: Increases your Attack stat by 10%, and decreases your Special Attack stat by 10%.
Naughty: Increases your Attack stat by 10%, and decreases your Special Defense stat by 10%.
Brave: Increases your Attack stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Defense
Bold: Increases your Defense stat by 10%, and decreases your Attack stat by 10%.
Impish: Increases your Defense stat by 10%, and decreases your Special Attack stat by 10%.
Lax: Increases your Defense stat by 10%, and decreases your Special Defense stat by 10%.
Relaxed: Increases your Defense stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Special Attack
Modest: Increases your Special Attack stat by 10%, and decreases your Attack stat by 10%.
Mild: Increases your Special Attack stat by 10%, and decreases your Defense stat by 10%.
Rash: Increases your Special Attack stat by 10%, and decreases your Special Defense stat by 10%.
Quiet: Increases your Special Attack stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Special Defense
Calm: Increases your Special Defense stat by 10%, and decreases your Attack stat by 10%.
Gentle: Increases your Special Defense stat by 10%, and decreases your Defense stat by 10%.
Careful: Increases your Special Defense Stat by 10%, and decreases your Special Attack stat by 10%.
Sassy: Increases your Special Defense stat by 10%, and decreases your Speed stat by 10%.
Natures that boost Speed
Timid: Increases your Speed stat by 10%, and decreases your Attack stat by 10%.
Hasty: Increases your Speed stat by 10%, and decreases your Defense stat by 10%.
Jolly: Increases your Speed stat by 10%, and decreases your Special Attack stat by 10%.
Naive: Increases your Speed stat by 10%, and decreases your Special Defense stat by 10%.
Neutral natures
Hardy: No effect.
Bashful: No effect.
Docile: No effect.
Quirky: No effect.
Serious: No effect.
If you want your Pokémon to have the highest speed possible, for example, you'll want it to have a 31 Speed IV and a nature that boosts Speed. This guide will also show you how to breed such a Pokémon.
Abbreviations Explained
If you find a group of letters, or one letter, it means that what follows works only for the games referred by those letters. The letters stand for the following:
R - Pokémon Ruby
S - Pokémon Sapphire
FR - Pokémon Fire Red
LG - Pokémon Leaf Green
E - Pokémon Emerald
D - Pokémon Diamond
P - Pokémon Pearl
SECTION TWO
How to discover the IVs of your Pokémon
You might think that the IVs of a Pokémon can be found rather easily among that particular Pokémon's stats. The truth is, the game conceals the IVs of your Pokémon, and rather well at that. So how can we discover the IVs of our Pokémon?
1. Estimation
When you breed a Pokémon and the egg hatches, the Pokémon will hatch at Level 5. (In DP, it hatches at Level 1. To make it Level 5, give it 4 Rare Candies.) Even at this low level, you can have a rough estimate of your IVs by looking at the babies’ stats if you know the base stats of that Pokémon.
At Level 5, if a particular stat is unaffected by the Pokémon's nature, that stat always has the following minimum and maximum numbers:
Minimum Stat = a + 5
Maximum Stat = a + 6, if b is between 0 and 4
Maximum Stat = a + 7, if b is between 5 and 9
where a is the base stat with the last digit removed and b is the last digit of the base stat. Moreover, if the stat is HP, add 10 to both the minimum and maximum stats.
If the stat is boosted by the Pokémon's nature and the stats above has more than one digit, add the first digit of that stat to it. For example, if the minimum stat calculated above is 8, then it stays 8. If, however, it is 16, add 1 (the first digit of 16) to 16, becoming 17.
If the stat is hindered by the Pokémon’s nature, first subtract the stat by 1. Then, if that resulting number has more than one digit, subtract it further by the first digit of that stat. For example, if the maximum stat calculated above is 10, then subtract 1 from it, becoming 9. Since 9 is a one-digit number, it stays 9. If, in another example, the maximum stat calculated above was 13, then subtract 1 from it, becoming 12. Since 12 is a two-digit number, we subtract it further by 1 (the first digit of 12), becoming 11.
Also, if your Pokémon has a maximum stat at Level 5, then:
If b is between 0 and 4, the IV for that stat is between 20 – 2b and 31.
If b is between 5 and 9, the IV for that stat is between 40 - 2b and 31.
The above information can be used to see roughly if the Pokémon’s IVs are bad, so that you can release it immediately if they are not good enough before proceeding to find the IVs more exactly.
Let's give an example. Suppose you have bred a Magikarp, and want to check if your Speed stat has a good IV or not. Let's assume that your Magikarp has a Jolly nature.
Magikarp's base Speed stat is 80. In our case, a = 8 and b = 0. So the minimum speed stat is 8 + 5 = 13. Since the stat is boosted by Jolly, we add 1 (first digit of 13) to 13, becoming 14. The maximum speed stat is 8 + 6 = 14. Again, since the stat is boosted by Jolly, we add 1 (first digit of 14) to 14, becoming 15. So, if the Magikarp's speed stat is 14, you can dismiss that Magikarp out of hand.
If the Magikarp has a maximum Speed stat of 15, then its IVs are in the range 20 - 2(0) and 31, i.e. between 20 and 31.
Let's give another example. Suppose you breed a Timid Treecko and you want it to have a high Special Attack stat. Treecko's base Special Attack is 65, so a = 6 and b = 5.
Its minimum special attack stat at level 5 is thus 6 + 5 = 11. Its maximum special attack stat is 6 + 7 = 13.
If your newborn Treecko has a special attack stat 11 or 12, then you dismiss it. If it has a Special Attack stat of 13, it means that its Special Attack IV is between 40-2(5) and 31; i.e. between 30 and 31 - a very good IV indeed.
The maximum stats of all the bred Pokémon at Level 5 can also be found in Part II, Section 5 of this breeding guide, for a quicker reference.
2. The Battle Frontier IV guy (only in E)
In Emerald, you can check your IVs by speaking to a man who lives in a house just above the Pokémon Center of the Battle Frontier. He will give you an overall judgment of all the IVs and the best IV of one of your Pokémon.
He will say the following:
“Ah, youngster! Do your Pokémon's abilities intrigue you? Here, here! Let's have a look at your Pokémon!”
You then choose the Pokémon that you need its IVs checked. He will then say:
"...Hmm...This one, overall, ..."
and then one of the following four:
"I would describe as being of average ability. "
-> the total of the six IVs is a number between 0 and 90 (average IV is between 0 and 15)
"I would describe as having better-than-average ability. "
-> the total of the six IVs is a number between 91 and 120 (average IV is greater than 15 but less than or equal to 20)
"I would say is quite impressive in ability!"
-> the total of the six IVs is a number between 121 and 150 (average IV is greater than 20 but less than or equal to 25)
"I would say is wonderfully outstanding in ability!"
-> the total of the six IVs is a number between 151 and 186 (average IV is greater than 25)
Then the man will proceed to mention the best IV that Pokémon possesses. If it has more than one best IV, this will be random. Talking to the man repeatedly will make him speak about the other equally best stats.
"Incidentally, the best aspect of it, I would say, is its (HP / ATTACK / DEFENSE / SPECIAL ATTACK / SPECIAL DEFENSE / SPEED) ..."
He then gives a judgment about that IV alone:
If the IV is between 0 and 15, the man will say: "That stat is relatively good."
If the IV is between 16 and 25, the man will say: "That stat is quite impressive."
If the IV is between 26 and 30, the man will say: "That stat is outstanding!"
If the IV is 31, the man will say: "It's flawless! A thing of perfection!"
The man will then finish up his monologue with the words: "...Hm... That's how I call it."
This Emerald feature is very handy to check if your Pokémon has a perfect IV.
3. IV calculator
If you prefer to just enter your stats in an IV calculator for it to work out the IVs for you, there are a few online programs that do just that. The best one is perhaps MetalKid's IV calculator, which can be found here. You input the stats of your Pokémon as you level it up with a few Rare Candies, and the program finds the IVs of your Pokémon for you. Refer to the actual site for more information.
4. Wi-Fi IV battles (DP only)
In DP only, if you battle against someone using the Wi-Fi connection, you can select an option to scale your battling Pokemon to Level 100. When this option is chosen, their stats are automatically calculated for Level 100, even though the Pokémon itself may not be a Level 100 one. This feature allows you to find the exact IVs of up to six of your Pokémon that have not yet battled, because, at Level 100, the IVs of the Pokémon can be calculated exactly in the vast majority of cases.
First, find a friend who is willing to let you check the IVs of all your Pokémon. (He or she might also want to do the same thing with his or her Pokémon.) Connect with him for a battle, and write down the stats of your Pokémon. When you’re ready, you and your friend simply run from the battle, and the battle ends.
The IVs can then be calculated as follows:
If the stat is hindered by the Pokémon’s nature:
IV = ceil(Stat * 10 / 9) – (2 * Base + Num) if Stat is not divisible by 9. If Stat is divisible by 9, then, unfortunately, the IV can be one of two numbers: either the one calculated here, or 1 more than that.
If the stat is boosted by the Pokémon’s nature:
IV = ceil(Stat * 10 / 11) – (2 * Base + Num)
If the stat is unaffected by the Pokémon’s nature:
IV = Stat – (2 * Base + Num)
where
ceil(x) is x rounded up. For example, ceil(5.6) = 6, ceil(18.01) = 19, and ceil(7) = 7.
Stat is the Pokémon’s stat at Level 100
Base is the base stat
Num is 110 if the stat is HP, and 5 otherwise.
For example, suppose you have just bred a Modest Chimchar which hasn’t battled yet, and you want to know its IVs. Let’s say that the stats that were noted during the Wi-Fi battle were the following:
HP: 210
Attack: 127
Defense: 97
Special Attack: 167
Special Defense: 102
Speed: 153
Chimchar’s Base Stats are:
HP: 44
Attack: 58
Defense: 44
Special Attack: 58
Special Defense: 44
Speed: 61
The HP IV is 210 – (2 * 44 + 110) = 210 – 198 = 12.
The Attack IV is ceil(127 * 10 / 9) – (2 * 58 + 5) = ceil(141.111) – 121 = 142 – 121 = 21. (Since 127 is not divisible by 9, this IV is exact.)
The Defense IV is 97 – (2 * 44 + 5) = 97 – 93 = 4.
The Special Attack IV is ceil(167 * 10 / 11) – (2 * 58 + 5) = ceil(151.818 ) – 121 = 152 – 121 = 31.
The Special Defense IV is 102 – (2 * 44 + 5) = 102 – 93 = 9.
The Speed IV = 153 – (2 * 61 + 5) = 153 – 127 = 26.
Of course, if you´re not able to calculate or simply don´t want to calculate the IVs this way, you can use Metalkid´s IV calculator (see above) to get your results.
5. Pokemon Characteristics (DP only)
This method does not provide the player with all of the Pokemon's IVs, but it does shed a very accurate light on the value of the highest IV of the Pokemon at a glance, which is very useful when breeding for 31 IVs in a particular stat. It is also useful when mass catching Ditto in DP since it provides a quick way of knowing if a Pokemon's highest IV is not 31.
DP introduced Pokemon characteristics, which is a short phrase that gives an idea on which is the stat with the highest IV of that Pokemon, as well as a rough idea of how high it is. The following is a list of all the Pokemon characteristics:
If the Pokemon's highest IV is in the HP stat:
Loves to eat - The HP IV's last digit is 0 or 5.
Often dozes off - The HP IV's last digit is 1 or 6.
Often scatters things - The HP IV's last digit is 2 or 7.
Scatters things often - The HP IV's last digit is 3 or 8.
Likes to relax - The HP IV's last dight is 4 or 9.
If the Pokemon's highest IV is in the Attack stat:
Proud of its power - The Attack IV's last digit is 0 or 5.
Likes to thrash about - The Attack IV's last digit is 1 or 6.
A little quick tempered - The Attack IV's last digit is 2 or 7.
Likes to fight - The Attack IV's last digit is 3 or 8.
Quick tempered - The Attack IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Defense stat:
Sturdy body - The Defense IV's last digit is 0 or 5.
Capable of taking hits - The Defense IV's last digit is 1 or 6.
Highly persistent - The Defense IV's last digit is 2 or 7.
Good endurance - The Defense IV's last digit is 3 or 8.
Good perseverance - The Defense IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Special Attack stat:
Highly curious - The Special Attack IV's last digit is 0 or 5.
Mischievous - The Special Attack IV's last digit is 1 or 6.
Thouroughly cunning - The Special Attack IV's last digit is 2 or 7.
Often lost in thought - The Special Attack IV's last digit is 3 or 8.
Very finicky - The Special Attack IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Special Defense stat:
Strong willed - The Special Defense IV's last digit is 0 or 5.
Somewhat vain - The Special Defense IV's last digit is 1 or 6.
Strongly defiant - The Special Defense IV's last digit is 2 or 7.
Hates to lose - The Special Defense IV's last digit is 3 or 8.
Somewhat stubborn - The Special Defense IV's last digit is 4 or 9.
If the Pokemon's highest IV is in the Speed stat:
Likes to run - The Speed IV's last digit is 0 or 5.
Alert to sounds - The Speed IV's last digit is 1 or 6.
Impetuous and silly - The Speed IV's last digit is 2 or 7.
Somewhat of a clown - The Speed IV's last digit is 3 or 8.
Quick to flee - The Speed IV's last digit is 4 or 9.
So if a Pokemon's IVs, for example, are 20, 13, 6, 19, 25 and 19 (in the order HP, Attack, Defense, Special Attack, Special Defense and Speed), then its characteristic would be "Strong willed" (the highest IV is in the Special Defense stat and its last digit is 5). If there are two or more equal highest IVs, the characteristic for that Pokemon will be for one of those stats at random. So, if, for example, another Pokemon's IVs are 24, 31, 17, 8, 0 and 31, then the Pokemon's characteristic will either be "Likes to thrash about" or "Alert to sounds".
As you can see, if the characteristic of a Pokemon is not one of the 6 marked in bold, then that Pokemon is sure not to have a 31 IV in any of the stats, and can be immediately released while breeding. Of course, if it is one of the bolded six characteristics, you still need to check that it is indeed 31, but the value of the stat itself after the Pokemon is given a few Rare Candies usually tells you immediately whether it is 31 or not.
This makes it much easier to check for 31 IVs in stats, which is a very important shortcut when breeding in DP. Unfortunately, the Pokemon characteristics are of little use to calculate the remaining 5 IVs of the Pokemon, so you'll still need to use one of the previously mentioned methods to discover them.
SECTION THREE
How the game provides IVs to an egg
Before we start our breeding guide, you need to be informed of how exactly the game assigns the IVs to a baby. This actually differs from game to game.
1. IV Breeding in EDP
The IVs for the baby are first created at random. Then, a random IV from either parent is inherited to the baby. Then, any random IV except an HP IV is selected from either parent and is passed to the baby. Finally, any random IV except an HP or Defense IV is selected from either parent and passed to the baby. These three random IVs may overlap, that is, the same random IV can be chosen to be inherited in the second, or third, IV transfer.
Let's give an example:
Parent A has the following IVs: 21, 7, 26, 15, 4, 10.
Parent B has the following IVs: 5, 3, 16, 30, 28, 20.
(These, and all IV sets that will be listed, are written in the following order: HP IV, Attack IV, Defense IV, Special Attack IV, Special Defense IV, and Speed IV.)
First, the baby's IVs are generated at random: 18, 0, 9, 14, 11, 27.
Then a parent's random IV is chosen, and passed to the baby. Suppose Parent A's Speed IV is chosen first. So now the baby's IVs are: 18, 0, 9, 14, 11, 10.
Then a parent's random IV (other than an HP IV) is chosen, and passed to the baby. Suppose Parent A's Defense IV is chosen.
So now the baby's IVs are: 18, 0, 26, 14, 11, 10.
Finally, a parent's random IV (other than an HP or a Defense IV) is chosen, and inherited to the baby. Suppose Parent B's Special Attack IV is chosen. And the baby's IVs thus become: 18, 0, 26, 30, 11, 10.
Note that the amount of IVs passed from the parents is not always 3, for the following two reasons. Firstly, the random baby IVs created at the start might match some of the IVs of the parents, which would seem as if the baby got passed more than 3 IVs. Secondly, two or three of the IVs passed to the baby might be in the same stat, which would seem as if the baby got passed less than 3 IVs.
This means that the baby will always inherit between 1 and 6 IVs from the parents. The chances are as follows:
1 IV: 2.44% chance
2 IVs: 34.41% chance
3 IVs: 53.01% chance
4 IVs: 9.55% chance
5 IVs: 0.58% chance
6 IVs: 0.01% chance
The majority of eggs (about 8 out of 9 eggs) will have 2 or 3 IVs transferred from the parents.
HP and Defense IVs are harder to inherit from the parents than the other IVs. This is different from the other games (see RSFRLG IV breeding), where each IV has the same percentage of being transferred to the baby (16.67%). The percentages for Emerald (and DP) are as follows (considering also the fact that the random IVs generated for the baby can end up to be the same as that of one of the parent's IVs):
HP: 8.02% chance of being inherited
Atk: 19.55% chance of being inherited
Def: 13.78% chance of being inherited
SpAtk: 19.55% chance of being inherited
SpDef: 19.55% chance of being inherited
Speed: 19.55% chance of being inherited
This means that in EDP, the Attack, Speed, Special Attack and Special Defense IVs have a better probability of being passed to the baby than in RSFRLG, while the HP and Defense IVs have a worse probability of being passed to the baby than in RSFRLG.
SUMMARY: Emerald, Diamond and Pearl
1. The baby’s IVs are created at random.
2. Then a random IV is passed from one of the parents to the baby. The previous IV is overwritten.
3. Another random IV from Attack, Defense, Special Attack, Special Defense and Speed is passed from one of the parents to the baby. The previous IV is overwritten.
4. Finally, another random IV from Attack, Special Attack, Special Defense and Speed is passed from one of the parents to the baby. The previous IV is overwritten.
2. IV Breeding in RSFRLG
The IVs for the baby are first created at random. Then, three random IVs from either parent are successively inherited to the baby. These three random IVs may not overlap, that is, the same random IV cannot be chosen to be inherited in the second, or third, IV transfer.
Let's give an example to make things clearer. Suppose the parents have the same IVs as before. Let's recapitulate:
The first parent (Parent A) has the following IVs: 21, 7, 26, 15, 4, 10.
The second parent (Parent B) has the following IVs: 5, 3, 16, 30, 28, 20.
First, the baby's IVs are generated at random: 18, 0, 9, 14, 11, 27.
Then a parent's random IV is chosen, and passed to the baby. This is repeated three times.
Suppose Parent A's Speed IV is chosen first. So now the baby's IVs are: 18, 0, 9, 14, 11, 10.
Then Parent A's HP IV is chosen. So now the baby's IVs are: 5, 0, 9, 14, 11, 10.
Finally, Parent B's Defense IV is chosen. And the baby's IVs thus become: 5, 0, 16, 14, 11, 10.
Note that the amount of IVs passed from the parents is, again, not always 3, but this time, there will always be at least 3 IVs that are passed to the baby. As before, though, the random baby IVs created at the start might match some of the IVs of the parents, which would seem as if the baby got passed more than 3 IVs. The chances for each of them happening are these:
3 IVs: 82.66% chance
4 IVs: 16.26% chance
5 IVs: 1.06% chance
6 IVs: 0.02% chance
SUMMARY: Ruby, Sapphire, Fire Red, Leaf Green
1. The game first creates the IVs of the baby at random
2. Then it overwrites three of the parents’ IVs to the baby, one after the other. These three parents IVs never overlap.
3. Probabilities for IV Breeding
Now, I think you're asking "What is the probability, given two parents with a few perfect IVs (31) in certain stats, for the baby to obtain those same perfect IVs in those stats?" To answer that question, the following applet was created, which can be accessed here.
You input the parent's IVs (you have only two choices for each IV: either it's between 0 and 30, or 31). Then click on whichever IVs you want the baby to be 31. Choose whether the game is RSFRLG (Ruby/Sapphire) or EDP (Emerald), and the applet will find the probability that the baby will have those 31 IVs, together with the amount of eggs you are expected to hatch in order to have such a baby. For example, in Emerald (and Diamond/Pearl), if both parents have a 31 HP IV, the baby has a 19.27% chance of getting a 31 IV in HP, according to the applet. For Ruby/Sapphire (and Fire Red/Leaf Green), the probability is much higher, at 51.56%.
Later on, in Part III of this guide (see link at the start of this part), a list of all the breeding combinations with their probabilities of inheriting IVs will be given. There, you can simply compare various methods of getting the desired IVs and save as much time as possible in the breeding process.
Credits
We would like to thank:
1) BobDoily for providing the IVs of many test eggs, which helped in the discovery of how the IVs of the eggs are generated.
2) loadingNOW for finding out how the game provides IVs to the egg by looking at the Ruby and Emerald ROMs.
3) MetalKid for his great IV calculator.