What is purity? Is it important? Are pure axies better? How does the game define purity? are pure axies more expensive?
Purity means that all cards on the axie belong to the class of the axie. This gives 10% bonus shield on the card value and 10% attack on the card value. Other classes using the same card won't get it. Secret classes (Dawn, Dusk, Mech) will get 7,5% instead but with 2 classes.
Purity is not part of the game, the only place where it matters is breeding the secret classes: Pure Aqua with pure Reptile has a chance to breed a Dusk. Pure Plant with pure Bird has a chance to breed a Dawn. Pure Beast with pure Bug has a chance to breed a Mech. Pure means all 6 dominant card have to belong to the class of body. The recessives doesn't have to be pure. I checked dusks, there are more than 30 generations since they became dusks. The first ones are not too strong, not super good either. scroll to the bottom of the page to see this in detail.
So why people refer to purity in other cases? Lots of youtubers started off with showcasing Freakkities axie extension. This helps you to see the genes of the axie on the marketplace. Higher purity means more cards belong to the class and the offsprings are pure, so it should be better in most cases. But it's not totally true and correlation doesn't imply causation.
The real reason to have some pure axies is to maximize their Health, Speed or Morale.
Usually nobody does it for the Morale. Sure, you get bug cards because they are strong, there are 0 cost cards for combos and slowdown, you get a side effect of critting more and class advantage. From s19, morale increases the crit damage, crit is no longer 2x the normal damage (almost 2x as it was combo bonus only once). So for certain builds like Ronin and Dual blade is worse having low morale, so low morale classes or unpure cards, as if they crit (ronin always crits in a 3 card combo) the damage is higher on high morale (dual blade gets double base attack on crits).
For health, you want a plant or dusk as the base stats are the highest so with 6 plant cards they will be the most healthy possible. That is 516 health points. Reptile cards also add 3 health but give speed, so this makes the tanks go faster and in their case it's a bad thing. So energy steal and generation, destroying, all forms of manipulation is better if it happens at the end of the rounds, otherwise they can steal it back.
Bug cards don't add speed, but only add 1 health (and 3 morale) so the tanks will be faster on same speed and lose out 2 stacks (12 health). One common build is Leafbug on plants. 61 stacks of health is 366 and 150 base for all axies, 516 total. With one bug card this is 59 stacks, 504 health. The pure one will attack later, making Serious more useful to steal the energy of the opponent and cactus deals 120% damage.
If two axies are same speed (pure vs pure or 2 leafbugs) then the health is checked first, the lower one goes last, so you got to keep your health higher. In case if health is equal the higher ID goes last, so the one that born later.
Same goes for attackers, only reverse. A pure bird will have 61 speed. So it's always faster than anyone else. The only exception can be another bird with a lower ID, so born before him. A bird with aqua card(s) is slower in case of equal speed as it gives more health to it. So until it takes damage it will be slower. And it's not a good thing to take damage with the class with the lowest health (other than self inflicted 30% with post fight card).
Click to expand.
The speed order also can be broken with speedups and speed downs. These will add up to 5 stacks of 20% each, which is calculated from base stats. 1 speedup=1 speed down. These cards are popular because they can outspeed other classes and change the attack order. Koi and goldfish are staple of the aquatic class, gives 3 speed and 1 hp to use one aqua card, koi needs another aqua card to be usable and it's on the tail so nimo can't be used (the only 0 cost which would make this 1 cost). Goldfish makes you faster for each incoming attack so it's a great defensive option as long as you survive. Arco only gives 1 speed instead of 3 but it's a beast damage, so you start on a lower speed, but it does not require a combo and i'm surprised there aren't many more aquas and mechs with it, won't worth it for dusks or reptiles as they get more damage from incisor. Arco is a horn card just as the lagging and incisor. But they slow down opponents instead. Making yourself faster is usually better, slowing down only works if you can target the axie that needs to be slower, which can be tricky as it needs direct hit, since slowing down removes 20%, big numbers lose more than what low numbers gain, usually it's 2 speed points, so there is an upside too. Croc and Incisor are decent damage and shield, while laggin is free so can be used each turn if you have it, especially on midline or back where it repeats after one of your axies die. There is a significant winrate change between reptiles/dusks under 46 speed or over 46, as one lagging won't make 45 speed faster than 57 but 46 is just enough. This means dusks on 46+ can attack aquas 6 times which is usually enough to kill with chomp.
What about the other classes then? When you use the cards for damage, then it gives 10% attack for being pure, 10% shield for being pure. So if it's not an attack card or defense, then it might worth for the utility. Cuckoo gives 20% attack on the next attack also cleans the stun, it costs zero, it has no damage on it's own. It's a bird card so it's fastest possible, there is no downside of using it for an axie that needs attack, if the other 3 cards are attacking cards, there is only a low chance that you run out of cards and don't have enough damage to finish off your opponent. Lagging slows the opponent down, also acts as a debuff which can be used for extra damage on thorny caterpillar.
Some classes like bird or beast got no healing cards. While their health is low so they won't get much chance to survive once hit, it's still an option to consider in some cases.
There are cards like Hermit, which is a big shield and disables critical attacks, rendering beasts useless against it. There are cards like Red Ear which is highest shield even when you lose out on the 10% shield from being pure.
There are many high damage horns, like Kestrel which is disabling horn cards on target, compared to Oranda, it's 139 vs 136 . But on the flip side, it changes the speed of the axie, so on same speed it's faster than a pure aqua, as it has 6 less health so it ignores the low vs high ID calculation. After s19 nerfs, kestrel is way better than most aqua horns, shoal star is now 126 from 134.
So 5/6 purity aqua is better than 6/6 purity when it's a bird card, especially on the horn. But 4/6 aqua with 2 bird cards is even faster. Sure, you can't go all the way, as you will lose a lot of health for being a bird inside an aqua body, also you can't find such a thing on the market.
Beasts or reptiles are 41 speed on default, so 42 speed is already an advantage. Aquas on 52 speed are faster than birds with one speedup. Dusks/Reptiles on 46 are faster than aqua on 57 speed and one speed down. Dusks/Reptiles on 49 are faster than birds on 61 speed and one speed down. If everyone is pure, having 1 extra speed can be enough to be faster in attack and gain advantage, these axies can sell on premium prices compared to others. 58 speed birds still outspeed aquas on default, so they can lose 3 speed (change a bird card with one bug or plant card) and still be fastest, only they won't be faster than other birds. 57 speed bird still outspeed aquas and can use 2 beast or 2 reptile cards while still having 57 speed so as long as they don't deal damage that bring the opponent under their own health they are faster.
These are things to consider when you looking for new strategies to beat others.
green is order for energy gain/tanks and red is order for attackers to go last/first
But since eyes and ears are not part of the cardset, they just add stats so they can be replaced right? I made a simple picture to explain which is the order. First step is deciding if it's a tank, an attacker or energy manipulator. A plant without serious, leafbug or carrot or watering can has no energy so it won't matter how fast it is, while plant cards will add health and shield, it's still good, but healing cards are better when you are not last. So for any axie the order is Plant, Bug, Reptile, Beast, Aqua, Bird when it manipulates energy. This includes Kotaro, Iguana, Antenna, Nimo, Imp, Goda, Rice, Cottontail too, nto just the plant cards. For any axie the order is Bird, Aqua, Reptile, Beast, Bug, Plant when it comes to attack. Notice it's exact reverse and adds up to 7. After s19 the hp and speed might not be the only way to choose eyes and ears. When morale worth nothing, it's easy to choose hp over it, now morale increases critical damage so shouldn't be ignored totally. For bugs, 1 beast card will keep the morale, reduce 1 hp but give 1 speed, this makes them always go first vs pure plants. No reason for going for speed, they won't ever reach other classes on 41, if they do, it isn't a bug anymore with 3-4 speed cards. For aquas in s19, even if speedups are good, goldfish got nerfed so there is a chance that higher armor or bug damage is more valuable. With koi or arco they still can have 52+ speed and fight birds but they deal more damage to plants, so unpure aquas got a lot better.
Also one of the most popular meta axie, the Terminator, which is Snail Shell/Tiny turtle/Laggin/Thorny Caterpillar is only using a single reptile card. And while most of termiantors are 3/6 purity, the best ones got bird/bird or bird/aqua or aqua/aqua eyes and ears so that's 16 to 50% purity.
Also when you choose a build like a terminator or a leafbug plant, your impure gene is not useless, so normal purity will be misleading as matching these impure parts makes it even better for breeding. https://elitebreeders.club/grading-system This link on the EBC website has a different take on the purity percentages which are closer to reality. The tool in the market analyzer also has a column called Cgrade which only targets cardsets, and goes from 00 to 44, where the first number is how many cards match the dominant gene from r1 and the second number is how many match from dominant the r2. So this works for finding printers better than a purity percentage that punishes the match of desired traits even more.
Sadly the speed coefficient can't be defined as a single number, it has too many parts, the class, the cards, even if you would add 3 points for each speed and remove 1 for each hp, the results would be misleading. There are 124 difference in speeds on the range of 31-61 based on combinations of cards. There are empty numbers and matching health/speed with multiple combos.
The other common mistake people do is defining axies value with their purity and ignoring other factors. "If I mix this 96% with a 93% will it be better than with two on 94%"? this type of questions don't make sense. If you look for a cardset, compatibility is key. those impurities not only have to be decent backup plans but also somewhat match the axies to have strong genes in a part to reinforce others if they are weak there. Each card is a separate layer, a box with 3 genes, when the parents mix, their genes mix, 6 for each row then 3 is selected, it's easy to get pure axies, but pure can mean random cards within your class, not necessary good ones.
So are pures better, more expensive? They are not better and shouldn't be expensive but it takes high risk to come up with good combinations within multiple classes so there aren't too many defined meta types for them and people keep it secret if they find one. Of course if something is really good then others will find about it faster. A lot of floor axies are mixed together and the results are usually really bad or really good toward pvp. So if you make some research on what combos are decent, there are some gems. So the pure options are just safer options, eventually we will have printers for everything.
These are one of the first dusks I could find. One branch was a totally normal pair of axies, not fully pure, only the dominants, they had 2 Dusk kids, 4 Aqua and 1 reptile. I guess the percentages are either 33-33-33 or 25-50-25. The new generation Dusk paired with another class seem to have 50-50 chance to become a Dusk. For what i saw this is slightly higher in reality.
9293 and 3552, one of the first Dusk parents
The other parents were similarly not impressive. 1 Dusk, 2 rep 2 aqua. But if you follow the children down the line you will see a lot of Christmas axies paired with them for the novelty of Christmas secret classes. Later people realized that dusks are useful for PVP too so slowly they cleared out the aqua cards and introduced bug cards and this is how the new duskinators were genetically engineered over 30 generations.