Analytics of gaming smart contracts by examining the Cryptokitties game. Part 1
CryptoKitties (www.cryptokitties.co) is one of the most popular games in the Blockchain network. It is based on the smart contracts of the Ethereum blockchain network. An example of a collection game with kitties has shown the value of ERC-721 tokens to the community and the possibilities of Ethereum as a playground.
In this research a team of analytics from Chaingraph.io attempted to conduct an extensive analysis of the decentralized application CryptoKitties, using the transactions extracted from the Ethereum network. The main analysis tool used is the smart contract analytical platform Chaingraph.
It is also worth adding that analytics is not just about the analysis of transactions, but also an attempt to understand and predict user behavior. The basis and purpose of the analysis is business, and the analytics should work for it. That is why many solutions from this report can be used for other decentralized applications of the crypto-game business sector.
For this study, the key issues were the increase of the audience for the DApp on the part of the developers and making a profit from the gameplay on the part of the player.
The contract that was analyzed is the main KittyCore contract (0x06012c8cf97bead5deae237070f9587f8e7a266d). We also used the data from the SaleClockAuction (0xb1690c08e213a35ed9bab7b318de14420fb57d8c) and SiringClockAuction (0xc7af99fe5513eb6710e6d5f44f9989da40f27f26) contracts.
Besides Chaingraph.io, the following services were used: Opensea.io, Bloxy.info and Dappradar.com. Data may have some inaccuracy.
Stats at the beginning of 2019
Market Cap: 40,000 ETH
Number of users (7d): 1,300
Number of users (24h): 450
Number of token holders: 70,000
Number of tokens in circulation: 1,500,000
Turnover: 57,000 ETH
Turnover (24h): 130 ETH
Number of smart contracts: 4
Twitter followers: 27,000
What is CryptoKitty?
Each kitty is a unique token that belongs to one holder. The uniqueness of a kitty is defined by its characteristics, or “cattributes”. The color of the paws, the shape of the whiskers, the length of the tail — all of this depends on the attributes obtained at birth. Besides the normal kitties with a set of certain characteristics there are also unique ones that look “not like everyone else” and possess exclusive arts/traits.
Types of Kitties
Normal — ordinary cats with a number of standard characteristics
Fancy — unique cats with a limited number in circulation.They can be created by cross-breeding using the right combination of genes at a certain time (alchemy). Such cats do not possess standard characteristics
Exclusive — these cats exist in the game only in one copy and they can not be bred. Every Exclusive cat is specially introduced into the game by the developers. Do not possess standard characteristics.
Special Edition — similar to Exclusive Cats in that they have unique art, but they are released in larger numbers and may be bought. Also do not have standard characteristics.
There are also some additional unique features:
Purrstige is a special characteristic cat obtained by cross-breeding by certain recipe.
Wild is a special wild element
Genetic Anomaly happens when the cat has a hidden gene that can suddenly appear in offspring
As you can see Exclusive cats are ahead of the rest. And the wild characteristic, on the contrary, is not decisive in defining the price for normal cats. It can be concluded that, despite its rarity, the wild characteristic is not very valuable.
Generations of cats
Cats are cross-bred and have such an option as a generation.
As you can see, the cats of the latest generations belong to one and the same player nicknamed Solidox, who is really far ahead. It looks like he wouldn’t be overtaken soon, since with the birth of nextcat’s generation, the cooldown after the breed-crossing increases. That is why the one who first has occupied a niche and is not going to yield it, is hardly probable to let somebody in.
Now let us consider the dependence of the average selling price on the generation of the cat, and also show the number of cats in each group.
As can be seen, after the 20th generation the number of kitties is significantly reducing, and with a three-digit generation their numbers tend to units.
Now let’s see the dependence on the selling price.
As you can see, after the 1000th generation the sales of cats are on the decline. Does it mean that after a fixed number nobody purchases? Let us study the sales of kitties of maximum generations.
The price of a cat depends on the cat itself but the generation does not really matter in its formation. The hypothesis about the guy who breeds the cats of the largest generation to earn seems to have failed. Unless he does not sell out them in some other way. It may be worth looking at buying crossings using the SiringAuction contract (the cats are not put up for sale, but one-time crossing with a cat :)).
As shown in the graphic above, the larger the generation is, the lower the price of breeding becomes. Kitties’ youth matters.
What cats with which characteristics are born most often and least often?
Normal cats have a set of cattributes that form their appearance. The direct logic suggests that the rarer any trait occurs, the more expensive the item is. Let us test this assumption.
Here are the rarest cats in the game. For defining the rareness of a kitty, the rareness of each characteristic matters and calculated by secret formula:
The cats above have not been purchased even once :)
If we, on the contrary, study the rareness of certain characteristics of kitties, that were marketed at least once, there won’t be any surprises:
The cost of rare kitties tends to the average price of all items.
Cattributes and their rareness are not so obvious for a player. Moreover, the traits that are considered to be the most pricy at the moment should show decrease in rareness, as the kitties with such cattributes will be bred more.
Now let’s take a look at the most expensive cats and at the same time quite rare:
The average rareness index of normal cats is about 3. The cats presented above possess the index 170+ (that is not the highest index, but is closer to maximum 500–800 than the 90% kitties). One may note that high price is formed due to additional rare elements (purrstige), or the combination of such characteristics, that accord kitties the more beautiful and catchy appearance. It can hardly be concluded about certain steady connection between the rareness and the price.
The following charts attest this. By each characteristic we observe approximately one and the same picture, namely sudden upsurge in certain rare trait. It should be mentioned that these spikes affect the price in no way.
What cats with which characteristics
do mate more often than others?
It is obvious that rareness of a kitty is inverse proportion to number of matings it has had. Let us consider the incidents with body type:
Still, if look at paid cross-breedings, we won’t see any connection between the rareness and the price again. The charts will look like the following:
That is, there are some upsurges with no logical reason to it.
Is there any correlation between the balance of a wallet and the number of kitty tokens that the user possess?
A great number of players who were involved into the game has either changed their accounts or just got rid of their kitties and stopped playing. The quantity of such users is estimated to be over 14000. Speaking about the existing accounts, with the increasing in the number of kitties the amount of players naturally and pretty quickly decreases:
1 kittie 8493 users
2 kitties 9749 users
3 kitties 10004 users
4 kitties 6346 users
5 kitties 4303 users
6 kitties 3265 users
7 kitties 2476 users
8 kitties 1887 users
9 kitties 1437 users
10 kitties 1204 users
11 kitties 935 users
Account balance dependence on the number of items possessed:
If account balance shows no regularities, then the connection between the number of tokens on ETH turnover is a little more vivid:
Here you may observe that the more kitty tokens the player possesses, the greater Ether turnover he has. Also let us compare the turnover of Kitty tokens and Ether:
The address (0xFC624F8F58DB41BDB95AEDEE1DE3C1CF047105F1) that had the biggest Ether turnover to the moment of research had about 3.5k kitty tokens on balance and its total kitty turnover was about 40k transactions.
It may be suggested that accounts with more than 1000 Eth of turnover will play the game more intensively, than the addresses having 500 Ether turnover.
Share your thoughts on the research, write comments, we’re ready to discuss :)
Part 2 will be soon!