CryptoKitties History – The Birthing Fee

Many players, both new and old alike, may not realize that the CryptoKitties birthing fee has not always been 0.008 ETH.

So here is a quick walk through the history of the birthing fee:

Nov 28, 2017: CryptoKitties launches with a birthing fee of 0.001 ETH
Dec 3, 2017: Birthing fee increased to 0.002 ETH
Dec 4, 2017: Birthing fee increased to 0.015 ETH
Dec 11, 2017: Birthing fee decreased to 0.008 ETH

Historical References

🚨🚨🚨🚨 Due to network congestion, we are increasing the birthing fee from 0.001 ETH to 0.002 ETH. This will ensure your kittens are born on time! The extra is needed to incentivize miners to add birthing txs to the chain. Long-term solution will be explored very soon! 🚨🚨🚨🚨

2:13 PM – 3 Dec 2017



1:25 PM – 4 Dec 2017

❤️❤️ We have dropped the birthing fee from 0.015 ETH to 0.008 ETH. Happy breeding everyone! 🐈

11:28 AM – 11 Dec 2017


Ralf Putmans (DerpyBastard) has graphed these birthing fee values against the ETH/USD price to chart the breeding price in USD over time (from November 28th, 2017 up through April 14th, 2018):

Birthing Fee

The average breeding price in USD over this entire time period is $6.06. Since the distribution of cats is skewed, the average amount spent to actually breed each kitty would be slightly different. You could overlay the births/day to calculate that number.

If you want to delve into the data, then please check out the Google Sheet that Derpy created:

About the Author

This article was written by Byzantinist (a.k.a. Byzantine Kitty), who is an expert on digital cat genetics. As a passionate aficionado of 100% 🐎 Purebred cats, Byzantinist runs a 🐎 Purebred Siring Shop that can be found here:

If you have any comments or feedback, you can contact me at or on Discord @Byzantinist – 🐎 Purebred Sires#2992


Check our Fancy Chasing Document (link in the sidebar) for all the details and hints as they come in.

Here are a few undiscovered fancies I’m aware of:

Butterfly Kitty

Mystery Fancy 2

Vernon – The Vernal Equinox Fancy

Mystery Fancy 1

Easter Fancy

Easter Fancy

In the recent Weekly Update video, Mack said the “Easter Fancy” was his favorite fancy so far.

See also: this week’s Update video.

Kitty411 Contest Fancy

This fancy was inspired by the Create-Your-Own-Fancy-Recipe Contest we had on Kitty411. We know that the recipe won’t be exactly the same as the ones submitted, and we’ll post further details about it as soon as we get them. I don’t think it’s one of the silhouetted fancies above, but I could be wrong.

Mad Scientist Fancy

(Leaked image on Twitter. Thank, CloudwhiteKitties, for spotting this for us!)

fancy leaked mad scientist

fancy leaked mad scientist 2

Fancy Hunting Event

On Thursday, April 12th, there is going to be a CryptoKitties event led by Jordan ( It will presumably involve fancy hints.

Check our Fancy Chasing Document (link in the sidebar) for all the details and hints as they come in.

Draco – The Green Dragon Fancy

Of course, we’re still waiting for Draco, the most famous and coveted of all fancy cats.

fancy draco



K4C Update / Bella’s Beauty Contest Results

The kitties that were donated to Kitties for a Cause (K4C) are now on sale HERE! They have exclusive balloons and were all given special names by Bella herself.

Earlier this week, we had a contest, Bella’s Beauty Contest, to promote K4C. Contestants sent in kitties, and Bella chose winners: 1st place, 2nd place, and 3rd place. She also selected four Honorable Mention kitties. Neither Bella nor Brian had any idea who donated any of the forty-two donated kitties. Here is the note from Brian with the results!

“Hi Jody,

Bella has completed the judging of Bella’s Beauty Contest. This was very exciting for her! This is the first time I have seen her skip her snack when getting home from school and head right upstairs to the office. I had to laugh when she looked at #589699 and said it looks like me when I get home from work.

Once she narrowed it down to the final three, it became very difficult for her to choose! But in the end she selected Strawberry Shortcake as the winner! She said she loved her eyes and also the fact that she loves to eat strawberry shortcake. Congrats to the winner and Bella is super excited to keep this beautiful kitty. We are going to make a separate account for Bella to keep her most prized kitties in.

We would like to offer a big thank you to everyone who contributed. Bella, as big-hearted as she is, was concerned for the people who submitted kitties she did not pick. She asked if they would be mad. I told her they may be disappointed, but not mad. They know the kitty will go towards a good cause and be adopted by another loving owner.

Here are the final results!”

1st Place: Strawberry Shortcake

bellas 1st

2nd Place: Sassy Selkirk

bellas 2nd

3rd Place: Sparklez’s Friend

bellas 3rd

Honorable Mentions:

bellas honorable mentions

The winning kitty, Strawberry Shortcake, will receive a gold medal and will be sent to Bella as a momento of her having the wonderful idea of using kitties to help others.

We were also going to send a gold medal to the owner of the winning kitty as their contest reward, but unfortunately, Strawberry Shortcake was donated after our official contest submissions were closed, thus making her owner (the one and only AlanFalcon) ineligible to receive the medal. (It would have been Alan’s second gold medal!) Alan had known that he missed the deadline and would be ineligible for the medal, but had sent in the kitty anyway as a kind-hearted, generous person. Thank you, Alan!

Since the gold medal can’t go to the first-place winner, it naturally passed to the second-place winner. And this is where things took a very unexpected turn.

The second-place winner, Sassy Selkirk, was donated by myself, Jody. I donated two kitties to the contest, but I honestly didn’t think either of them were going to win. I was surprised by the results and was quite confuddled as to what to do. I never anticipated being able to win a Kitty411 gold medal because I usually have to disqualify myself from every contest I run (even though I want a medal as much as anyone). But since this was a contest in which I had no part in judging, and since I submitted the kitties anonymously and according to the rules, I’ve suddenly found myself in a position where I legitimately won a gold medal! So I’m going to go ahead and give Cookie (my Kitty411 mascot) the gold medal from this contest. 🙂

Thank you, everyone, for participating in Kitties for a Cause! And make sure you buy a kitty from the K4C account to get your balloon momento!

gold medal on cookie
For reals this time!

Byzantinist is joining Kitty411!

I’m so happy to announce that Byzantinist (a.k.a. Byzantine Kitty) will be helping me on Kitty411 from now on! Many of you have probably already met Byzantinist through Discord or the Purebred Shop, and seen how knowledgeable, helpful, and upbeat Byzantinist is. I’m so excited to have that as an official part of Kitty411 now!

As always, if you see anything on Kitty411 that needs updating, please feel free to let one of us know. or Discord @Byzantinist – 🐎 Purebred Sires#2992 or Discord @Jody –

Check out Byzantinist’s first article: All About Cattributes.


All About Cattributes

UPDATE: My discussion about terminology with Alanfalcon has spurred the adoption of several new terms among the CryptoKitties staff, which you might see them use in the near future. Instead of dominant (D0) and recessive genes (R1/R2/R3), they might refer to active (A0) and hidden genes (H1/H2/H3) for normal cats and H0/H1/H2/H3 for fancy cats. In addition, they prefer classifying genes found in Generation 0 cats as Level 1 while Wingtips is a Level 3 gene (instead of using the “Tier” keyword).

Every cat has a cattribute/trait in 8 different categories which each has an impact on the visual appearance of the cat (except for Fancy cats). There are also 4 additional categories which are normally hidden.

If you do not understand basic CryptoKitty genetics, including how dominant and recessive genes work, then I recommend you start with some older CryptoKitties411 articles:

The 8 primary cattribute categories are:

  • Fur / Body
  • Pattern
  • Eye Color
  • Eye Shape / Type
  • Base Color
  • Highlight / Pattern Color
  • Accent / Secondary Color
  • Mouth

One detail that is often missed is that the background of the cat image is determined by the Eye Color of the cat.

There are also 4 additional hidden categories. Basic Wild genes do not seem to do anything but Tier 1 Wild mutations (e.g. Elk, Trioculus) are additional cattributes which are displayed and impact the visual appearance of the cat. At this time, it is not known what Mystery, Secret, and Unknown genes do, though there is plenty of rampant speculation of what they might do.

Fancy cats of a given type all have the same physical appearance though the background color does change depending on Eye Color. Fancy cats are assigned a numbered Fancy badge instead of having cattributes displayed. However, they still have relevant dominant and recessive traits which can be passed down to their offspring. And while none of their family or mewtation jewels are displayed, these still exist and can be passed down as well.

Not all cattributes are the same. Some are much rarer or more valuable than others. To help you better understand the nature of cattributes, here are some broad categories that are sometimes used. Most of these terms are used colloquially (instead of there being an official definition) so there may be slight differences in meaning or usage.

Normal / Base Traits

“Normal” often means the standard traits that do not fit in any of the other categories (not mutations, retired / discontinued, or founder traits).

Sometimes, “Base” trait is used to refer to all non-mutation traits (which may include retired / discontinued and founder traits). So Jaguar might be considered a “Base” trait but not a “Normal” trait.

Founder Traits

The first 100 cats are the Founder cats and they are each assigned a special Founder badge. Every Founder cat has the following genetic makeup for their dominant and recessive genes:

Fur: Himalayan, Munchkin, Ragamuffin, or Sphynx
Pattern: All Founders are 100% 🐎 Purebred Jaguar
Eye Color: Chestnut, Mintgreen, Sizzurp, Strawberry, or Topaz
Eye Shape: Crazy, Simple, or Thicccbrowz
Base Color: All Founders are 100% 🐎 Purebred Orangesoda
Highlight Color: Chocolate, Coffee, Lemonade, Royalpurple, or Swampgreen
Accent Color: Granitegrey or Kittencream
Mouth: Beard, Happygokitty, Pouty, or Soserious

Jaguar is a special case because among Generation 0 cats it can only be found among the original 100 founders. That means that any higher generation cat with a Jaguar gene is a descendant of at least one of the Founder cats.

Beard, Chestnut, and Simple are also notable cases because the only Generation 0 cats with dominant Beard, Chestnut, or Simple are some of the Founder cats. These genes may appear in non-Founder Generation 0 cats but only as recessive genes.

The traits listed above are collectively called Founder traits because they were present in those original cats. However, these genes can be found in other Generation 0 cats as well (except no Beard, Chestnut, or Simple as dominant and no Jaguar at all).

Since jewels were introduced much later, Founder traits are also notable because they do not have associated jewels (no diamond, gild, amethyst, or lapis). This can be an important consideration for players who want 8 jewel or 9 jewel cats.

There are also some additional jewel-less traits that are often considered Founder traits even though none of the 100 Founder cats technically had any of these genes:

Pattern: Luckystripe, Totesbasic F, and Totesbasic G
Base Color: Aquamarine, Greymatter, Salmon, and Shadowgrey

These cattributes can be found in some of the earliest cats (e.g. Bug Cat exclusive, 500-number cats) and other low number cats (e.g. Knight Kitty exclusives).

Retired / Discontinued Traits

Over time, some traits are phased out and no longer appear in new Generation 0 cats. These are referred to as “Retired” or “Discontinued” traits. Note that this is not an official designation. There is nothing to prevent Axiom Zen from including these genes again in upcoming Generation 0 cats but that has not happened so far.

An older list of Discontinued traits can be found here:

Discontinued Traits

I do plan to write an article in the near future to update the list of Retired / Discontinued Traits.

“Recessive” Traits

Recessive traits (which is different than recessive genes) is sometimes used to refer to traits that show up in recessive positions (R1, R2, or R3) in Generation 0 cats but are not expressed (D0) in any of those cats. The only way for these genes to become dominant is to breed the cats until gene swapping causes them to move into the D0 position.

The following traits can be found as recessive genes but not dominant in Generation 0 cats:

Fur: Chartreux and Savannah
Pattern: Calicool, Camo, Ganado, and Spock
Eye Color: Doridnudibranch and Forgetmenot
Eye Shape: Baddate, Otaku, Serpent, and Stunned
Base Color: Dragonfruit, Harbourfog, Hintomint, and Nachocheez
Highlight Color: Apricot, Barkbrown, Lilac, Poisonberry, Scarlet, Springcrocus, and Violet
Accent Color: Belleblue, Emeraldgreen, Missmuffet, and Peach
Mouth: Belch, Gerbil, Wasntme, and Whixtensions

Since it requires gene swapping to get these traits into a dominant position, it is rarer to see these cattributes expressed among low generation cats.

Furthermore, some recessive traits are rarer than others. For example, Chartreux can only be found in the R3 position of Generation 0 cats while Camo can be found in R2 or R3, and Otaku can be found in R1, R2, or R3.

As a result, for Generation 1 cats, a Chartreux is rarer than a Camo, which is rarer than an Otaku, which is rarer than a normal trait like Totesbasic or Granitegrey.

I will be going into more depth on these recessive traits in an upcoming article.

Mutation Traits

When two cats breed, certain pairs of traits can mutate into a new trait. For a primer on mutations, please take a look here:


Mutation traits simply do not appear in Generation 0 cats as dominant or recessive genes. So if you see something like this:

You know there is something wrong because Tigerpunk is a mutation and Otaku is a recessive trait so neither should be dominant in a Gen 0 cat. If you actually look at this cat’s genetic code, you will see that its Pattern is really Totesbasic F and its Eye Type is Thicccbrowz. So this is a front-end bug with the website.

It takes time for mutations to propagate so low generation cats with mutations can be extremely valuable and 🐎 Purebreds are not even possible until several generations have passed.

Note that there is some variance with terminology. Most people seem to refer to Cloudwhite as a Tier 1 mutation and Wingtips as a Tier 2 mutation. However, there are some people who refer to all base traits (non-mutations) as Tier 1, which would make Cloudwhite Tier 2 and Wingtips Tier 3. Furthermore, Alanfalcon has been advocating the use of “ascension” instead of “mutation.”

About the Author

This article was written by Byzantinist (a.k.a. Byzantine Kitty), who is an expert on digital cat genetics. As a passionate aficionado of 100% 🐎 Purebred cats, Byzantinist runs a 🐎 Purebred Siring Shop that can be found here:

If you have any comments or feedback, you can contact me at or on Discord @Byzantinist – 🐎 Purebred Sires#2992


An Announcement

Thank you to those who participated in the Kitty411 Create-Your-Own-Fancy-Recipe Contest! I LOVED the submissions! It was impossible to judge them because they were all so wonderful, so I randomly choose a winner from the entries.

The winner was Maine Coon Love for her submission for a raccoon kitty! The gold medal will go her kitty that most closely resembles a raccoon.

Here’s another bit of news for you: The CryptoKitties team also loved your creative submissions! In other words, there will be a contest-inspired fancy cat coming soon! (I’ll let you know if they give me more details about it.)

Please note that the contest-inspired fancy cat is UNRELATED to our winner. I chose our Kitty411 winner independently of them, and they chose their fancy cat independently of me. They did not know that the raccoon would be our winner, and I have no idea which fancy kitty they may be making. All I know is that their fancy kitty will probably look a lot like one of our entries to the contest.