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The Layman's Guide to EVs, IVs, and Natures [Version 2]
The Layman's Guide to EVs, IVs, and Natures
Note: This is a guide spanning many posts. Do not post in this topic until I end a post with the phrase, "YOU MAY NOW POST". Please respect this rule.
Table of Contents
-- I: So, what is an EV?
-- II: How do EVs influence my Pokemon's stats?
-- III: Alright, so how do I train my Pokemon's EVs?
-- IV: EV training takes too much time! Can I speed it up?
-- V: I messed up my EV training! Is there a way to reset my Pokemonís EVs?
-- I: So, what is an IV?
-- II: How do IVs influence my Pokemon's stats?
-- III: How can I get better IVs for my Pokemon if they're impossible to change?
-- IV: Breeding changes IVs? How?
-- V: How can I check my Pokemon's IVs?
-- VI: Is there any way I can get an estimate of my Pokemon's IVs without resorting to fancy calculators or Wi-Fi battles?
-- I: What was that part about Natures? What are you talking about?
-- II: What about that RNG abuse thing you mentioned earlier? What's that?
5: History of EVs and IVs
7: Credits and Thanks
Welcome to Aeres116699's guide to EVs, IVs, and Natures. This topic is designed to inform those who have not a clue about the lesser-known mechanics of the Pokemon games, and as such, will only focus on the basics. I will not go into intricate detail about making effective EV spreads, IV breeding, or RNG abuse how-tos, as those topics merit a closer look from someone more qualified than I. This guide will merely cover the essentials.
Without further ado, on we go!
2 - I: So, what is an EV?
An EV, or Effort Value, is a certain value that helps to determine the growth of your Pokemon's stats. Every time your Pokemon gains experience from a battle, EVs will be given to certain stats depending on its opponents. There are 6 types of EVs, one for each stat: HP, Attack, Defense, Special Attack, Special Defense, and Speed; different Pokemon will provide different EVs upon defeat. This means that along with level-ups gaining stats, the EVs acquired by your Pokemon will also influence how much the stat goes up.
Wow, does this mean I can get unlimited EVs and max out my Pokemon's stats?
Not exactly. See, a Pokemon can only have 510 EVs; once it hits that number, any further battles will fail to grant EVs. On top of that, a Pokemon can only hold 255 EVs in one stat; while this gives you enough to fill up 2 stats with EVs, it's far from reaching 999 in all stats. However, these EVs can and will play a vital role in your Pokemon's battling efficiency.
2 - II: How do EVs influence my Pokemon's stats?
For every 4 EVs in a particular stat, your Pokemon will gain 1 additional stat point. Since a stat can have 255 EVs total, and a Pokemon can have 510 EVs overall, this means a Pokemon can receive a maximum of 63 extra stat points in one stat, and 127 extra points across the board.
127 total? But 63 times 2 equals 126! Where'd the extra point come from?
The simplest EV setups (known as "EV spreads") involve maxing out 2 stats by investing 255 EVs into both. However, you'll notice that 255 is not divisible by 4. Since Pokemon games round down, this means that both of those stats will have 3 "leftover" EVs that serve no purpose. Fortunately, there's a way to make use of those 6 total leftover EVs.
Instead of investing 255 EVs into a stat, invest only 252. (I'll go into how to invest EVs later on.) This frees up the 3 leftover EVs for use. While 3 EVs will not do anything by themselves, investing only 252 into the other stat gives you 6 that you can use. Four of those EVs can be invested into a third stat, giving you a single stat point boost; some people find this pointless, but I believe it's best to make as much as you can out of EVs. The final 2 EVs are useless, and do not matter (unless you're doing complicated multi-stat EV spreads, which I will not go into).
Here's an example: I have a Pikachu I want to train to be a fast special attacker. Naturally, I would want to invest EVs into Special Attack and Speed. I could take the lazy route and just put 255 EVs into both stats, but if I chose to invest 252 into each instead, I could put the final 6 EVs into its HP stat to give Pikachu just a tad more survivability. It's not much, but every bit helps.
2 - III: Alright, so how do I train my Pokemon's EVs?
EV training is a method used to accurately control which EVs your Pokemon gains, in order to complete your ideal EV spread. This process involves repeatedly battling and defeating certain wild Pokemon until you obtain the desired EVs from them.
How do I tell which Pokemon give which EVs?
Since every Pokemon has a different amount of EVs that it rewards, there is simply not enough space in this guide to list every one. Instead, I will provide a link to Bulbapedia, a Pokemon fansite that elaborates on the matter.
That list is too long! Are there any noteworthy Pokemon that give EVs in certain stats?
Thanks to the diligent work of Tygore001 and company, I now have a reliable EV hotspot list to show. Note: All of these hotspots require the HM03, Surf, to reach.
- Where: Cliff's Edge Gate
- What to do / How to get there: It's the cave just west of Cianwood City, with the woman behind the counter advertising for the Safari Zone. Surf around in the little pond in that cave. (Rock Climb required)
- What you're looking for: 90% chance of finding Wooper (grants 1 HP EV), 10% chance of finding Quagsire (grants 2 HP EVs)
- Where: Mount Mortar
- What to do / How to get there: Enter the middle cave from Route 42, on the plot of land where the trio of Apricorns can be found. Once inside, Surf around the big lake; don't go down the ladder.
- What you're looking for: 90% chance of finding Goldeen (grants 1 Attack EV), 10% chance of finding Seaking (grants 2 Attack EVs)
- Where: Route 21
- What to do / How to get there: Surf south from Pallet Town until you see a relatively large plot of land with lots of tall grass. Run around in there.
- What you're looking for: 90% of finding Tangela (grants 1 Defense EV); ignore everything else
Special Attack Hotspot:
- Where: Route 35
- What to do / How to get there: Head north from Goldenrod City and Surf around on the small lake where the Apricorn tree is.
- What you're looking for: 90% chance of finding Psyduck (grants 1 Special Attack EV), 10% chance of finding Golduck (grants 2 Special Attack EVs)
Special Defense Hotspots:
- Where: Route 40 (percentages in bold, Route 41 (percentages in italics
- What to do / How to get there: Either Surf east from Cianwood City, or south from Olivine City; Surf around in the ocean.
- What you're looking for: 90% / 60% chance of finding Tentacool (grants 1 Special Defense EV), 10% / 30% chance of finding Tentacruel (grants 2 Special Defense EVs), 10% chance of finding Mantine (grants 2 Special Defense EVs)*
- Where: Route 43, Route 45, Blackthorn City
- What to do / How to get there: Surf on any body of water in those three areas.
- What you're looking for: 100% chance of finding Magikarp (grants 1 Speed EV)
*Mantine can only be found on Route 41, as a HeartGold exclusive.
Finally, it has been brought to my attention that wild Ditto can also serve as handy EV training. Thanks go to hotdogturtle, who first mentioned this technique to me:
Ditto copies the EV reward (the number of EVs granted upon defeat) of the Pokemon it Transforms into. So, if a wild Ditto Transforms into a player's Dragonite, defeating the Ditto in that Transformed state will grant 3 Attack EVs, just like an actual Dragonite would. It's therefore possible to exploit this quirk by putting the Pokemon you plan on EV training first in your party (remember to use Power Items and Pokerus if possible; these will be discussed in a bit). When you find a Ditto, switch to a Pokemon in your party that has the EV reward you want your first Pokemon to gain, and defeat the Ditto.
For example, suppose I have an Absol I want to EV train in Attack. I equip a Power Bracer (again, discussed later), put it in my front party slot, and put a Dragonite into my party as well. When I find a Ditto, I switch Absol out and send Dragonite in. Ditto will Transform into Dragonite; at this point, I'll defeat the Ditto to gain Attack EVs for Absol! This is a handy trick for speeding up the EV training process, as most Pokemon with high EV rewards are either rare or impossible to find in the wild.
Route 47 has a 41% chance of encountering Ditto, and there's a chance of having a daily swarm of them in the same location, increasing their appearance rate even more.
The game will tell you how many EVs you have, right?
Unfortunately, no. Youíll have to manually keep track of the EVs your Pokemon has gained by writing them down in a notepad or something as you go. Since the game doesn't tell you how many EVs your Pokemon has gained, you'll need to keep track yourself, which is tedious, but necessary.
The exception to this lies in the Effort Ribbon. Iím told that somewhere in Blackthorn City, a lady will give your Pokemon an Effort Ribbon if that Pokemon has obtained the maximum 510 EVs. This is a good way to make sure that you havenít miscalculated the number of battle you have to fight.
I wanna EV train my level 100 Mewtwo so that it can pwn my friends!
Thatís the problem with EV training: From levels 1 to 99, you can take as much time as you need to EV train... but once that Pokemon hits level 100, youíre out of luck. This is because EV gains boost stats upon level-up (but not immediately; the results are not obvious at first, but will be far more noticeable at level 100 than they would be at, say, level 35). Since a level 100 Pokemon cannot level up anymore, it is impossible to EV train them. Make sure to get your EV training done before that point.
2 - IV: EV training takes too much time! Can I speed it up?
Fortunately, there are a number of ways to make EV training go faster, as many find it to be quite tedious. There are a number of items you can use to speed up the process:
Vitamins: Most people recognize that the vitamin items (HP Up, Protein, Iron, Calcium, Zinc, and Carbos) raise your Pokemonís stats when used. What isnít as widely known is that the vitamins do so by raising your Pokemonís EVs! Every vitamin will award your Pokemon 10 EVs in a given stat, depending on the vitamin. This allows you to get a head start on EV training by simply buying vitamins and using them for early EV training. Unfortunately, once a stat gains 100+ EVs, vitamins will no longer have an effect; on top of that, vitamin training gets expensive quickly. Still, itís incredibly useful to stock up on vitamins when you get around to EV training.
Here's a quick list showing which vitamins give what EVs:
HP UP: 10 HP EVs
Protein: 10 Attack EVs
Iron: 10 Defense EVs
Calcium: 10 Special Attack EVs
Zinc: 10 Special Defense EVs
Carbos: 10 Speed EVs
Power Items and the Macho Brace: To someone unaware of how EVs work, these items seem useless. When equipped to a Pokemon, they halve the Pokemonís Speed in battle. Thatís only their side effect, though: theyíre really used for gaining EVs faster, and are therefore almost essential for mass EV training.
The Power Items are bought at the Battle Frontier for 16 BP each. When equipped, they give the Pokemon in question a boost of 4 EVs in a certain stat, on top of the EVs they gained normally. Hereís the chart:
Power Weight: 4 HP EVs
Power Bracer: 4 Attack EVs
Power Belt: 4 Defense EVs
Power Lens: 4 Special Attack EVs
Power Band: 4 Special Defense EVs
Power Anklet: 4 Speed EVs
So, suppose Iím training my Pikachu from a few paragraphs up. Iím starting with training EVs in Special Attack. If I equip my Pikachu with a Power Lens, and battle Gastlys over and over (which give a single Special Attack EV), Pikachu would gain 5 Special Attack EVs total for every battle; the single EV from the Gastly, and the 4 EVs from the Power Item bonus. This also applies when my Pikachu is fighting a Magikarp, which gives a single Speed EV. My Pikachu would gain 1 Speed EV, and 4 Special Attack EVs.
The Macho Brace is similar to the Power Items, in that the Pokemon holding the item has its Speed halved in battle. Unlike the Power Items, however, the Macho Brace doubles all EVs earned instead of adding a fixed amount of bonus EVs per opponent. Therefore, if my Pikachu held a Macho Brace while training for Speed EVs on Magikarp, it would gain 2 Speed EVs every battle instead of 1.
For those of you wondering, the Speed decrease from the Power Items and Macho Brace do NOT affect stat gains for Speed; itís simply an in-battle effect.
Exp. Share: While the Exp. Share doesn't increase EVs directly, it can help to EV train weaker Pokemon who otherwise wouldn't be able to train at the EV hotspots themselves. Since any Pokemon that gains experience also gains EVs, slapping an Exp. Share onto one of your Pokemon will basically give it EVs without having to fight! Unfortunately, the Exp. share disregards EV boosts from the Power Items and Macho Brace, meaning that even if the Pokemon you're using to fight has one of those two items equipped, the Exp. Share holder will still only gain the base EV reward from the wild Pokemon defeated.
Pokerus: This is a weird one. It's a virus that is obtainable by battling a wild Pokemon who happens to be infected by it. Unfortunately, there's no way to tell whether or not a Pokemon you're fighting actually has it, and the odds of finding one that does are worse than that of finding a wild shiny. However, if you do find it (or trade for a Pokemon with it), it is extremely helpful for EV training, as it doubles all EV gains by the Pokemon. Not only that, but it doubles the EV gains AFTER the gains from a Power Item or Macho Brace are calculated, so that the static EV boost from the Power Item is also doubled, as well as the Macho Braceís doubling factor.
Pokerus is identified on a Pokemon by checking its "Summary" tab in the party / PC; if it has the condition, it should have a purple block next to its portrait. This means the Pokemon is "infected" and will gain double EVs. Battling with this Pokemon in your party gives a chance of spreading the virus to other party members, much like a real virus.
Thereís something to keep in mind about Pokerus, though. If a Pokemon goes for 24 hours in your party with the "infected" status (even if you're not playing), it will then change to the "cured" status, indicated by replacing the purple block with a yellow smiley face outlined with red. This status is exactly the same as the "infected" status, with the exception that a Pokemon with the cured status cannot infect other Pokemon ever again. In addition, a cured Pokemon will never again be able to revert to the infected status. This is generally a bad thing, because if you run out of Pokemon to transmit Pokerus, you'll have to find it again somehow to continue the cycle. Therefore, you want to somehow preserve an infected (NOT cured) Pokemon so that you can spread Pokerus whenever you want.
By leaving it in the PC, that's how. Storing a Pokemon in the PC will reset the 24-hour countdown to the cured status, as well as prevent the timer from counting down for as long as it's in the PC. This means you can have a "dummy" Pokemon in your PC for the sole purpose of transmitting Pokerus to other Pokemon as you see fit. Pokerus will not spread to other Pokemon in the PC, though, so don't expect it to do your work for you.
2 - V: I messed up my EV training! Is there a way to reset my Pokemonís EVs?
Thankfully, there is one option you can take if you messed up. There are certain types of Berries that, when given to a Pokemon, lower a certain statís EVs. Hereís the list:
Pomeg Berry: Subtracts HP EVs
Kelpsy Berry: Subtracts Attack EVs
Qualot Berry: Subtracts Defense EVs
Hondew Berry: Subtracts Special Attack EVs
Grepa Berry: Subtracts Special Defense EVs
Tamato Berry: Subtracts Speed EVs
Feeding a Pokemon a single Berry of this type will lower the statís EVs down to 100, no matter how many EVs were in the stat. If the EVs are at 100 or below, every use of the Berry will subtract 10 EVs until all the EVs have been removed from the stat. Avid Pokemon Trainers may find it handy to grow a decent supply of these Berries in case they screw up an EV spread.
But where can I get the Berries in the first place?
HeartGold and SoulSilver don't let you pick Berries from trees, like you could in the previous games. Because of this, actually getting the Berries you need can be annoying. Thankfully, there are two methods you can use to gain all the Berries you need.
Remember those colored Shards from Platinum? The red, blue, green, and yellow ones that you traded in to learn moves from the Move Tutors? In HGSS, they're now used to buy Berries! After finding the Shards (from using Rock Smash on rocks), you can turn them in to one of two individuals in the game. One of the NPCs, who have Juggler sprites, can be found in front of the Violet City Pokemon Center, and the other can be found amongst the Fuschia City flower beds. That second Juggler is the one who hands out the Berries we need.
Unfortunately, the Juggler doesn't give every EV-reducing Berry. That's where the Pokewalker comes in! You can find the remaining Berries on the Big Forest Pokewalker course after a set amount of steps, using the Dowsing Machine function.
Here's a small chart detailing which Shards go to which Juggler to get EV-reducing Berries:
Pomeg Berry: Give Fuschia Juggler a Red Shard
Kelpsy Berry: Give Fuschia Juggler a Blue Shard
Qualot Berry: Pokewalker Course: Big Forest (4,500+ steps)
Hondew Berry: Give Fuschia Juggler a Green Shard
Grepa Berry: Give Fuschia Juggler a Yellow Shard
Tamato Berry: Pokewalker Course: Big Forest (1,000+ steps)
The IV Guide starts here.
3 - I: So, what is an IV?
An IV, or Individual Value, is a value that determines the maximum amount of stat points that a Pokemon can gain. Like EVs, IVs will influence the amount of points a Pokemon can gain in any one stats. Unlike EVs, however, IVs are not gained through battle. The system can be compared to genes in a living being, in that IVs are determined upon encountering a wild Pokemon or hatching one of your own Pokemon.
Wait, what does this mean?
Simply put, once you find a Pokemon in the wild, or hatch an Egg, the IVs for that Pokemon are set in stone immediately, and are impossible to change or alter. This is the key difference between EVs and IVs: EVs can be directly adjusted by the player, while IVs cannot.
3 - II: How do IVs influence my Pokemon's stats?
Like EVs, there is an IV value for each stat: HP, Attack, Defense, Special Attack, Special Defense, and Speed. Once a Pokemon is encountered (through a wild battle, hatching an Egg, or any other means of obtainment), each IV in a stat is randomly given a value ranging from 0 to 31. A stat with an IV of 0 will only be able to gain the minimum amount of stat points in that area, while an IV of 31 will gain the maximum. The IV value in a stat is the additional amount of stat points your Pokemon will gain as it levels from 0 to 100.
I'm so confused...
I'll provide an example, then. Suppose I find a wild Pikachu. I catch the Pikachu, and after calculating its IVs (I'll explain this later in the guide), I find that it has the following IV setup (known as an "IV spread", just like with EVs):
Special Attack: 30
Special Defense: 0
Discounting EVs for the moment, I know from this table that when my Pikachu reaches level 100, its Attack stat will be 2 points higher than another level 100 Pikachu with an Attack IV of 0. Likewise, the Pikachu I found will have a Speed stat 31 points higher than that of another Pikachu with a Speed IV of 0!
As you can see, IVs play an integral role in calculating stats. That's why it's near-essential to get the best IVs you possibly can, especially if you're a competitive battler fighting other players. Not only that, but IVs also determine the type and power of a Pokemon's Hidden Power, so it's important to consider IVs for that purpose as well.
3 - III: How can I get better IVs for my Pokemon if they're impossible to change?
In truth, there are three main ways to attempt to get better IVs for a Pokemon:
3: RNG abuse
The first of the three is self-explanatory, so I'll discuss the other two.
3 - IV: Breeding changes IVs? How?
As mentioned before, a Pokemon's IVs are determined upon encountering it in the wild, on the field (i.e., a legendary that is stationary and allows you to interact with it to start the battle, like Ho-oh), or from hatching an egg. Unless you're incredibly lucky, have the patience of a saint, or use RNG abuse, you won't be getting decent IVs from the first two. Breeding, however, is a different story.
It turns out that when Pokemon are bred, some of their IVs are passed down to the child Pokemon (think Punnett squares from biology class). Through breeding, you can pass down the IVs you want, and even influence which ones to a certain degree. It's possible, although tedious, to use the breeding method to eventually create a Pokemon with perfect IVs (31 IVs for all stats) without cheating!
How do you go about doing this?
Unfortunately, going into detail about breeding for IVs is outside the scope of this guide, as it is quite a broad topic. I'll go over the basics, though.
Before you even begin breeding, you'll want the following:
- A Ditto (preferably with good IVs)
- A Power Item corresponding to the stats you want your baby Pokemon to inherit its parents IVs from (discussed further in a little bit)
- A Pokemon in the same evolutionary chain as the one you wish your IV-bred Pokemon to be (if you want an IV-bred Charmander, this would be anything in the Charmander evolutionary tree)
Note: For this guide, I'll assume you already know the basics of how to breed and hatch eggs. If you do not, consult a different FAQ for breeding.
I'll set up another example here. Suppose I want a Pikachu that has good IVs in Special Attack and Speed. For this, I'll bring along a Ditto (preferably with good IVs in Special Attack and/or Speed), a Pikachu / Raichu (with the same preference as the Ditto), a Power Lens, and a Power Anklet.
Let's assume our Ditto and Raichu have the following IVs for this example:
(In terms of the following template of HP/Attack/Defense/Special Attack/Special Defense/Speed)
Raichu: 11 / 23 / 1 / 31 / 7 / 9
Ditto: 2 / 28 / 15 / 0 / 24 / 30
Now, if I just threw Raichu and Ditto into the Day Care Center and hope for a badass baby Pikachu, I'd be here for a while. Notice how Ditto's Speed IV is high, while its Special Attack IV is low? Raichu has the same thing going on in reverse. Just slapping the two in the Day Care wouldn't be very effective, as the IV inheritance system would likely screw me up.
IV inheritance system?
That's the way a bred Pokemon gets its IVs from its parents. Basically, the baby's IVs are generated randomly, like a wild Pokemon would. Then, a random IV from either of the parents is given to the baby; the inherited IV is substituted for the first generated IV. This happens three times, meaning that a newly hatched Pokemon will have three completely random IVs, and three taken from its parents. Unfortunately, the inherited IVs can overlap, so it's possible for a baby to inherit the same three stats from the same parent, effectively only inheriting one stat.
Are there limitations to the inheritance system?
Yes, actually. The first of the three IV inheritances has no restrictions. However, the second of the three cannot have the HP IV from either parent transferred. The final transfer cannot have either the HP or Defense IVs from either parent given to the child.
Can we get back on track with the example?
Take a look back at Ditto and Raichu's IV spreads. We want a Pikachu with high Special Attack and Speed IVs, but the Ditto has a high Speed and low Special Attack value, while the Raichu has a high Special Attack and low Speed value. Leaving the IV inheritance up to chance alone would be inefficient. This is where my Power Items come in.
A new feature introduced in HeartGold and SoulSilver involves using the Power Items in breeding. If a Pokemon is equipped with a Power Item, the stat corresponding to that item will have its IV transferred to the baby, guaranteed. This is very useful for getting one or two excellent IVs, so we'll use this method. I'll equip Raichu with the Power Lens to transfer its Special Attack IV, and Ditto will hold the Power Anklet for its Speed IV. Now we can pop the two into the Day Care and start getting some eggs hatched until we find a Pikachu with the right IVs.
Note, however, that if you equip both of your parents with Power Items, the IV inheritance system may still overlap the inherited IV for that stat, negating the Power Item's effect. This is purely random, so if it happens, just keep hatching. It's also worth noting that you can't equip the Everstone to the parents if both hold Power Items, so you can't transfer Natures effectively either (I'll go into Natures in a little bit).
3 - V: How can I check my Pokemon's IVs?
IVs are a hidden part of the game, and as such, cannot be directly checked. However, there is one way to get information about IVs...
By using an IV calculator, such as this one.
Upon hatching your Pokemon, write down the stats it has. Then, level it up once WITHOUT BATTLING so that you don't get unwanted EVs (to do this, either use the Day Care or some Rare Candies). When your Pokemon levels up, check and record the stats at that level. Continue leveling the Pokemon and recording the stats of each level until level 10. At that point, you have enough information to enter into the calculator and gain a relatively accurate readout of your Pokemon's IVs.
[This message was deleted at the request of the original poster]
There are two variant methods to calculating IVs in this manner. If you bring your newly hatched Pokemon into a Wi-Fi battle after recording its stats at level 1, it will be temporarily leveled to 50 or 100, depending on your battle mode. Record the stats of your Pokemon at this point, finish the battle (by forfeiting), and enter them into the calculator for a far more accurate readout. By doing this, you don't have to worry about the Day Care or Rare Candies at all. Alternatively, Wii owners can upload their Pokemon onto Pokemon Battle Revolution for the same result.
3 - VI: Is there any way I can get an estimate of my Pokemon's IVs without resorting to fancy calculators or Wi-Fi battles?
Actually, yes; there are 2 methods of doing this. First off would be the Characteristics of a Pokemon. Characteristics are those little snippets of text in your Pokemon's summary box, such as "Likes to run", or "Hates to lose". While this might seem to be mere flavor text to the unaware, these lines actually indicate your Pokemon's best IV, and the general potency of that IV (as in how good it is). Keep in mind that Characteristics only note your highest IV; they don't give an exact figure for how high it is, only a range. Therefore, if your Pokemon has a 0 in all IVs except HP, which is 1, you'll get an HP characteristic since it's the highest, even though it's still only 1.
The following is a list of Characteristics, sorted by stats for which they are relevant.
Likes to relax;
Often dozes off;
Often scatters things;
Scatters things often;
Loves to eat
Likes to fight;
Likes to thrash about;
A little quick tempered;
Proud of its power
Capable of taking hits
Special Attack Characteristics:
Often lost in thought;
Special Defense Characteristics:
Hates to lose;
Quick to flee;
Somewhat of a clown;
Alert to sounds;
Impetuous and silly;
Likes to run
What about that second method of determining IVs ingame?
The Pokemon Judge can be found in the Battle Tower of every game since Emerald. He can provide an estimate of how good your Pokemon's IVs are across all stats, as well as determine the Pokemon's best IV and how high it is. Similar to the Characteristics, the Judge won't tell you what your IVs are in the usual "0 - 31" sense, but will give you phrases that indicate the extent of your Pokemon's IVs.
Average IV count:
This Pokemon's potential is decent all around -- Low IV count
This Pokemon's potential is above average overall -- Average IV count (don't be fooled by the tidbit he gives)
This Pokemon has relatively superior potential overall -- High IV count
This Pokemon has outstanding potential overall -- Very high IV count
Best IV explanations:
Rather decent -- Low value
Very good -- Good value
Fantastic -- Very good value
It can't be better in that regard Perfect value (31)