PreprintPDF Available

Blockchain Games: A Survey

Preprint

Blockchain Games: A Survey

Abstract and Figures

With the support of the blockchain systems, the cryptocurrency has changed the world of virtual assets. Digital games, especially those with massive multi-player scenarios, will be significantly impacted by this novel technology. However, there are insufficient academic studies on this topic. In this work, we filled the blank by surveying the state-of-the-art blockchain games. We discuss the blockchain integration for games and then categorize existing blockchain games from the aspects of their genres and technical platforms. Moreover, by analyzing the industrial trend with a statistical approach, we envision the future of blockchain games from technological and commercial perspectives.
Content may be subject to copyright.
Blockchain Games: A Survey
Tian Min, Hanyi Wang, Yaoze Guo and Wei Cai
School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, China
Email: {tianmin, hanyiwang, yaozeguo}@link.cuhk.edu.cn, caiwei@cuhk.edu.cn
Abstract—With the support of the blockchain systems, the
cryptocurrency has changed the world of virtual assets. Digital
games, especially those with massive multi-player scenarios, will
be significantly impacted by this novel technology. However, there
are insufficient academic studies on this topic. In this work,
we filled the blank by surveying the state-of-the-art blockchain
games. We discuss the blockchain integration for games and
then categorize existing blockchain games from the aspects of
their genres and technical platforms. Moreover, by analyzing
the industrial trend with a statistical approach, we envision the
future of blockchain games from technological and commercial
perspectives.
Index Terms—Blockchain, Game, Decentralization, Applica-
tion, Software, Survey.
I. INTRODUCTION
THE blockchain system [1] became one of the most
promising technologies since late 2017, nine years after
the release of Satoshi Nakamoto’s famed Bitcoin whitepaper
[2]. In addition to the classic application of distributed public
ledger, blockchain is now recognized as the foundation of
decentralized applications (DApps) [3]. Ethereum [4], known
as the Blockchain 2.0 platform, is designed to facilitate smart
contracts [5], which are open source programs that can be
automatically executed without any centralized control. How-
ever, the blockchain ecosystem is still struggling with the lack
of killer applications. In fact, the initial coin offering (ICO)
has been the most public recognized DApp since Ethereum
starts its token business. Nevertheless, numerous ICO scams
and valueless “air tokens” brought a disreputable impression
on the emerging technology.
The digital game has the potential to be the rescue of the
blockchain. It perfectly fits the nature of the virtual currency
ecosystem since it does not have the data entry pollution
problems that commonly exist in many other DApps. In fact,
the blockchain system fulfills the ultimate dream of many
game players: the items they owned in the virtual world are
non-fungible, exchangeable, inheritable, and independent to
the game service provider. In this paper, we would like to
formally define the term of blockchain games: the series of
digital games designed and implemented based on the nature
of blockchain technologies.
Following are the major benefits blockchain has brought to
the game industry. Rule Transparency: Due to the transparent
characteristic of blockchain data, players or third-party organi-
zations can audit the smart contract based games rules, which
was hidden in the centralized server in traditional games.
The transparent game rules will enhance the trustworthy of
the game operation. Asset Ownership: In traditional online
games, the virtual properties, including credits, items, and
avatars, belong to game operators since all data are stored
in the game operators’ server. In contrast, the blockchain
game player owns their game assets, because all virtual assets
will be bound to the players’ own address, which allows
the players to control and manage everything. The ownership
enables the game assets to be independent of specific game
operators, which allow the players to retain their digital
properties and in-game relationships, even after the game stops
its operation. Thanks to the ownership feature, virtual assets in
the blockchain ecosystem have tremendous market liquidity.
The possibility of asset trades across different games and
blockchain platforms stimulates the players to better engage in
the game economy. Moreover, the liquidity enables potential
new profit model for game operators: the value of the assets
will be increased if the demand surpasses the supply, which
should be restricted by immutable smart contracts. The game
operators may benefit from the value increase of the tokens
they issued. Assets Reusability: Intrinsically, the blockchain
is an open database that hosts data and executable programs.
Game developers can leverage blockchain to design an ecosys-
tem that allows players to reuse their characters and virtual
items across different games. To this end, newly launched
games can directly inherit game assets from the existing ones.
User-Generated Content (UGC): UGC in traditional games
are restricted in the specific game, thus, belongs to the game
operator. In contrast, these contents can be preserved by the
players, thus, has the potential to be shared among multiple
games. This benefit will, in turn, encourage the players to
participate in the construction of new content.
According to the above advantages, the industry has started
its venture on integrating blockchain into gaming systems. The
Blockchain Game Alliance1was formed in September 2018
to explore alternative uses of blockchains in video games. In
contrast, there is still a blank in academia to study the impact
of blockchain on the future form of games. In this work, we
survey the state-of-the-art blockchain games and analyze their
trend from a statistic approach. The remainder of this paper
is organized as follows. We briefly introduce the blockchain
technology in Section II and illustrate the system architecture
for blockchain game in Section III to provide an overview.
Afterward, We survey the state-of-the-art blockchain games
by categories in Section IV. We also perform data analysis to
summarize and predict the future trend of blockchain games
1http://blockchaingamealliance.org/
978-1-7281-1884-0/19/$31.00 ©2019 IEEE
in Section V. Section VI concludes the article and envision
the future of blockchain games.
II. BACKGROU ND : BLOCKCHAIN
By definition, a blockchain is a continuously growing chain
of data blocks, each of which contains a cryptographic hash
of the previous block, a time-stamp, and its conveyed data
[1]. Due to the existence of the cryptographic hash, the data
stored in a blockchain are inherently resistant to modifica-
tion: if one block of data is modified, all blocks afterward
should be regenerated with new hash values. This feature of
immutability is fundamental to blockchain applications. The
blockchain data structure, together with the peer-to-peer (P2P)
system and the proof-of-work (PoW) [6] consensus model,
makes the decentralized ledger for cryptocurrencies became a
reality [2]. On this basis, smart contracts, the programs hosted
and executed by the blockchain platforms, process business
logic in a transparent and autonomous way. By leveraging
smart contract, blockchain games enable data storage and key
functionality execution while avoiding the services of a game
operator.
III. BLOCKCHAIN GAME ARCHITECTURE
Fig. 1 illustrates the architecture for conventional blockchain
games. Different from traditional games, the blockchain
game players should register an address in the correspond-
ing blockchain before they start their gaming sessions. This
blockchain address, accessed by a wallet program later, will
serve as the destination of virtual assets for its corresponding
player. On the other hand, the game server should offload
some core functions, e.g. the ones manipulating the players’
virtual assets, to the blockchain as smart contracts. These smart
contracts are open source programs written in the blockchain.
Fig. 1: Architecture for Blockchain Games
From the perspective of the blockchain, to support digi-
tal games implies high-performance requirements, including
transactions per second (TPS), response latency, etc. Conven-
tional blockchain adopting Proof-of-Work (PoW) [6] consen-
sus models, e.g. Ethereum, failed to satisfy these needs. Hence,
some new consensus models have been proposed by novel
blockchain platforms, including EOS2, Tron3, Neo4, Qtum5,
Nebulas6, etc. In this paper, we mainly focus on Ethereum
and EOS, since they have the largest market cap among all.
IV. CATEGORY OF BLOCKCHAIN GAM ES
To illustrate an overview of commercial blockchain games,
we briefly introduce 23 representative games from various
platforms in this section. These games are classified into 4
categories by the major benefits brought by blockchain.
A. Rule Transparency
The rule is the most critical element of a game since all
players are making their choices based on the preset rules.
However, not all games rules are transparent to the players,
since they are always hidden in the centralized game server.
For example, the production of random numbers, commonly
used in determining the delivery of virtual items through a
lottery, is usually unsupervised. The game developers tend to
claim a higher winning probability in order to attract players,
while the players can not audit the process. This issue became
more critical when the value of virtual items increased. In
blockchain games, critical game rules can be implemented as
smart contracts to guarantee their transparency. In this way, the
players can supervise the lottery smart contracts and prevent
developers from arbitrarily altering lottery functions. Appar-
ently, the transparent characteristic of blockchain improve the
trustworthiness of the games, especially for those ones requires
high reliability, e.g., online casinos.
Satoshi Dice7; Bitcoin; 4/2012: Launched in 2012 as the
very first gambling game on the blockchain, Satoshi Dice
contributed more than half of all the Bitcoin transactions. The
rules are simple: first, players send Bitcoins to the jackpot,
a certain neutral address on the blockchain, to place their
bets on a number. Second, the system will randomly choose
a lucky number. If the chosen number is smaller than the
lucky number, players win, otherwise, they lose. Although
the game mechanism is simple, it’s a milestone to blockchain
gamification.
PoWH 3D (Proof of Weak Hands 3D)8; Ethereum;
2/2018: A Ponzi Scheme running on Ethereum. Players use
ETH to buy tokens, the first token costs 0.0000001ETH. The
price will be 0.0000001ETH higher when another token is
bought. If a token is sold, the price will be 0.0000001ETH
lower. Each deal will charge a 10% commission fee for both
the buyer and the seller. This fee will be averagely distributed
2https://eos.io/
3https://tron.network/
4https://neo.org/
5https://qtum.org/zh
6https://nebulas.io/index.html,
7https://satoshidice.com/en
8https://powh.io
among the token holders. Smarts contract can prevent Ponzi
bankers from escaping with the money. PoWH 3D triggered
a Ponzi heat on Ethereum. Many similar games flow into the
market, such as PoWL, PoWC, PoWD and so on. It’s called
a “Clone War”9of P3D games.
FOMO 3D10; Ethereum; 7/2018: It is one of the most
famous blockchain Ponzi Schemes, with the highest jackpot of
3 million dollars. The game has a 24 hours countdown. Once a
player buys a new key, it will add 30 seconds. Meanwhile, the
cost of the keys will get higher. When the countdown touches
0, which means there is no more new key buyer, the last buyer
of the key will get 48% of the jackpot. Rest of the jackpot
will become a bonus that distributes to all shareholders with a
proportion linked with the number of the keys they hold. It’s
one of the most remarkable blockchain game on Ethereum.
BetDice11; EOS; 9/2018: The player will roll a dice: if the
selected number is smaller than the result, the player wins,
otherwise loses. The target number is chosen between 1 to
100 by a smart contract to ensure fairness. BetDice is one of
the most popular DApps on EOS at the end of 2018. Because
it’s run on the EOS chain, there is no gas fee or time delay,
which attracted much more players than casinos on Ethereum.
FarmEOS12; EOS; 10/2018: FarmEOS is a virtual casino
that combines various gambling games like Baccarat, Keno
and Roulette together. It has a shareholder system to offer a
dividend. By the end of 2018, FarmEOS had 29,000 weekly
active users and transaction volume of 6.6 million EOS. In the
meantime, EOS-based gambling games experienced explosive
growth: 147 out of 240 games on EOS are gambling games13.
These highly homogeneous games contributed over 90% of
transaction volume.
TRONBet14; TRON; 10/2018: TRONBet is a gambling
game based on TRON blockchain platform where the players
can gamble with TRX, the token of TRON. The game has 3
modes, Roll, Moon and Ring. In the Roll mode, the players
can adjust the slide to change their prediction of the lucky
number. In the Moon mode, the player needs to escape before
time elapses to get a reward. In the Ring mode, the players
need to guess the color of a random wheel. Another dividend
mechanism is that once the players bet, they can get ANTE, the
token of Tronbet. They can freeze ANTE to receive dividends
from Tronbet. ANTE can also be transacted in exchanges.
B. Asset Ownership
User agreements in the conventional games usually state the
players’ right to use the game account, but lack of emphasis on
the ownership of the virtual properties. In contrast, blockchain
game players have more genuine ownership of their virtual
properties. Blockchain games allow players to trade their game
properties into cryptocurrencies that can be circulated around
9https://coincryptonews.com/tag/p3d-clones/
10https://exitscam.me/play
11https://www.betdice.one/
12https://www.farmeos.io/
13https://DAppradar.com/rankings/protocol/eos/category/gambling
14https://www.tronbet.io/
the internet. What’s more, the game items will not only be
valuable in a particular game.
CryptoKitties15; Ethereum; 11/2017: CryptoKitties is a
simulation game about breeding, collecting and trading kitties,
which are actually indivisible and unique ERC-721 tokens.
The operations on kitties like selling and breeding are func-
tions implemented in the smart contracts. The game has a
web application interface to help players better interact with
Ethereum. As one of the most famous blockchain games
launched in November 2017, it has caused a great sensation:
the rarest kitties worth more than one million dollars. It created
a record of 40,000 active users in one day, and once jammed
the Ethereum network. Till the second year in April, the total
turnover reached 43,067.04 ETH, which is about 200 million
dollars. However, it has many drawbacks. The most criticized
point of the game is the poor game experience. Many people
consider it as a blockchain fund plate rather than a game.
In addition, its playability is limited: even Tetris has more
fun then CryptoKitties. According to the recent statistics from
DAppRadar16, the transaction volume has dropped to only 1%
of the peak value, only 4,000 of 720,000 rare kitties were sold,
and less than 1,000 players remain active.
Etheremon17; Ethereum; 12/2017: Etheremon is a
blockchain edition of Pokemon, which overcame CryptoKitties
in terms of playability. Players can capture, train Etheremon,
and participate in combat with each other. Similar to Cryp-
toKitties, every Etheremon is a unique token. Its developers
focus on balancing the game and improving the gameplay.
Many new models like monster types and skill system were
added in order to make the game more interesting. Although
the extra parts may not be completely implemented on smart
contracts, these efforts made Etheremon ranked at the top 5
Ethereum games for a long period.
EtherGoo18; Ethereum; 4/2018: After the success of “Hot
Potato” Mode and pet cultivation games, simulation and strat-
egy games like EtherGoo emerged. At the beginning of the
game, players own a factory and a cat, which will earn you
resources: Goo. Players use Goos to upgrade their factories or
buy different types of cats. A reward will be given to the most
productive player every day. What’s more, players can send
their cats to attack other factories in order to plunder resources.
In the early May of 2018, the game successfully reached
the top three blockchain games with the largest transaction
volume: more than 200 ETH transactions in 24 hours. Due
to its popularity and the big success, TronGoo19 has been
launched on TRON blockchain platform in January 2019.
Gods Unchained20; Ethereum; 7/2018: Gods Unchained
is a blockchain card game, who is similar to the traditional
TCG (Trading Cards Game) like Hearthstone21. In traditional
15https://www.cryptokitties.co/
16www.DAppradar.com
17https://www.etheremon.com/
18http://ethergoo.io/
19https://trongoo.io/
20https://godsunchained.com
21https://playhearthstone.com
TCGs, players purchase cards from the game operators, who
can infinitely issue cards. In Gods unchained, each set of cards
are issued by smart contracts in limited quantity. Therefore,
the players can only trade cards with others if the packages
have sold out. Gods Unchained is one of the most successful
blockchain game in 2018 summer. It has exquisite characters
and fancy animations, which helped it earned more than 1.3
million dollars in half a month, according to the announce-
ment from its official website. However, Gods Unchained is
unfriendly to the players who cannot spend much money on
games because of the high price of its cards.
0xUniverse22; Ethereum; 7/2018: 0xUniverse creates a vir-
tual universe where players can build spaceships, explore the
galaxy, and colonize planets, which are all digital collectibles.
The discoverers will extract resources and carry out research
that allows them to conquer the remotest corners of the galaxy.
In addition, players can jointly contribute to the story and
unravel the mystery of the universe.
EOS Knights23; EOS; 8/2018: Developed by a Korean
team, EOS Knights is the first mobile game that runs on EOS.
Players can fight with Goblins, the monsters in the game,
using their own characters. If the characters die, the game
will settle items players earned during this expedition. Players
can trade, craft, and equip more than 55 kinds of items and
weapons. The more weapons equipped on the characters, the
more powerful they will be, and the more reward players will
get after each game. Compared to previous blockchain games,
EOS Knight’s user interface is much more gorgeous and the
interactive latency is much smaller thank to the Delegated
Proof-of-Stake consensus model in the EOS platform. EOS
Knight attracted over 500 players once it launched and the
number has increased to more than 5,300 up to the end of
201824, which make it one of the most popular blockchain
games.
EOSDOTA25; EOS; 1/2019: EOSDOTA is a PVP trading
card game. Players will select three heroes to form a team.
Each hero has its own rarity, type and combat power. In every
single round of a game, players need to designate one hero
to battle. The damage caused by a hero is randomly chosen
between 1 and its combat power. Players can gain hero cards
in three ways: 1. directly buy cards from the developers; 2.
attend championship contest; 3. win cards from other players
in plunder mode.
HyperSnakes26; Ethereum & TRON; 5/2019: Hyper-
Snakes is the blockchain version of the famous multi-player
online game Slither27. Players control a snake which can grow
longer by collecting dots or eating smaller snakes in the arena.
To make the game more interesting, developers are going to
add a number of features such as shields, speed boosts and
more. These power-ups can greatly help a player to survive in
22https://0xuniverse.com
23https://eosknights.io
24https://DAppradar.com/eos/652/eos-knights
25https://www.eosdota.com/
26https://www.hypersnakes.io/e/d/d/index.html
27Slither.io
the arena. HyperSnakes adopts a free-to-play model and pay-
to-play rooms where players are able to compete with each
other and earn rewards in cryptocurrency for their performance
in the game.
C. Asset Reusability
In contrary to the centralized database server of traditional
games, the blockchain is a more open platform for game
developers. The players’ data can be accessed by smart con-
tracts or a set of application programming interfaces (APIs).
Although there is still tons of work to be done, including
setting up a stable economic system and consistent numerical
design for multiple games, it is exciting to imagine if a player
can use his/her own character in RuneScape28 to continue
adventures in World of Warcraft29. Brought by CryptoKitties,
KittyVerse is a game asset reuse project aiming to build an
ecosystem spreading kitties in more blockchain games. The
project has released a license called Nifty30 for developers who
are interested in reusing the CryptoKitties assets. Followings
are some of them.
KittyRace31; Ethereum; 3/2018: KittyRace is a blockchain
game that reuses the assets from CryptoKitties. It allows Cryp-
toKitty owners to race their kitties against others for Ethers.
According to the whitepaper, a kitty’s hustle is determined by
three digital dice rolls: a provably fair random roll, genetic
makeup, and position. The first is purely random, the second
is determined by specific attributes of the players’ kitties, and
the third is affected by the order in which the player joined the
race (the first two kitties to join get a slight advantage). The
race will be started by calling the KittyRace smart contract
after the players pay their entry fee. The player who executes
the contract will be reimbursed in the form of 10% of the
initial fee.
KittyBattle32; Ethereum; 12/2018: KittyBattles is a kitty
combat game that lets players’ form their kitties into a team
and battle other teams with water balloons, pillows and other
deadly items. According to their blog, KittyBattles conducts
the battles off-chain to reduce the overhead of Ethereum smart
contract invocations. While KittyBattles is intended as a turn-
based player-vs-player game, the game is still in alpha and we
had a hard time finding real people to battle with.
KotoWars33 ; Ethereum; 12/2018: KotoWars invites the
players to fill decks with their cryptokitties and then try to
reduce opponents health points to zero. Each CryptoKitty is
assigned a defense score, an attack score and an element.
The first two parameters depend on the cat’s attributes at
CryptoKitties, and the elements will introduce a magical sys-
tem that diversifies the gameplay. One game session requires
at least 32 CryptoKitties to be started, but if the player
doesnt have enough they can use computer-generated cards
28https://www.runescape.com/splash
29https://worldofwarcraft.com/en-gb/
30https://www.niftylicense.org/
31https://kittyrace.com/
32https://alpha.kittybattles.io/
33https://kotowars.com/
instead. Another interesting feature is that the KotoWars ties
into KittyHats34, another KittyVerse-based game so that the
customized hats that the players bought in KittyHats will
appear in the game.
D. User-Generated Content
UGC is any form of content that has been posted by
users rather than the developers/operators on online platforms.
UGC in games keeps updating the game elements, which is
critical in retaining veteran players. In contrast to traditional
game communities like Steam Workshop35 , storing UGC in
blockchain emphasizes the ownership of the created item
and the intellectual property of the author. Thus, it helps
remove commercial intermediary to provide an open source
community atmosphere.
Cell Evolution36; Nebulas; 5/2018: It is a unique game
that uses blockchain to form a player community. Each player
in this game act as an individual in a huge population of cells.
In this population, cells need to balance several attributes to
survive. In the game, players decide their evolution strategies
through four buttons: reproduction, evolution, mutation, and
dormancy. Each click on buttons is one round of a game.
Players need to explore the evolution and mutation pattern to
gain a higher score by surviving longer and reproduce more
cells. As the round number increase, the game will get harder.
Players can update their DNA information into “the worlds”
when his game is over. This is actually uploading data to the
blockchain. There are 8 worlds in this game. Every players’
DNA will affect the survival of the entire population. Only
balancing the attributes can survive. The attributes’ balance
check is defined as follows: balance check = (a+s+r)/3,
where ais adaptivity, sis survivability and ris reproductivity.
For each component in the balance check, it should fall
between 0.5 and 1.5 of balance check, otherwise, the world
will collapse.
CardMaker37; Nebulas; 7/2018: CardMaker is a UGC
game that “focuses on content design, battles, and trading.”
The players are alchemists who use their own cards to partici-
pate in turn-based combats. In CardMaker, the game developer
only creates game frameworks and basic rules, while the
players are encouraged to design their own cards, characters,
levels, and trade them to gain the upper hand in battles and
achieve their goals in the game. Under the token economy,
the players can vote all the design, the content, the update
and the designer if they like. Also, the players can share and
trade their self-designed cards with other players.
Last Trip38; Ethereum & TRON & Nebulas; 10/2018:
Last Trip is a storybook in which the players will experience
a series of events through a journey. The players need to
select their actions to the events, and their choices may apply
negative or positive influences on their avatars’ attributes. The
34https://kittyhats.co/
35https://steamcommunity.com/workshop/
36http://www.cellevo.net/
37https://www.cardmaker.io/
38http://lasttrip.matrixDApp.com
players need to improve their avatars’ attributes to win the
battles. After the game is over, the player can submit his avatar
data to the blockchain, which enables the avatar to be the part
of the story in future journeys. In Last Trip, the developer
only provides the basic framework of the story, while the
participating players continuously contribute their content to
the game itself.
Adam’s Venture39; Ethereum & TRON & Nebulas;
3/2019: Adam’s Venture is a multi-player Dungeons and
Dragons (D&D) novel-adventure game. In this game, the
players will experience three modes: Battle of Adventure,
Battle of Dark Lord, and Battle of Blood Moon. In the
Battle of Adventure mode, massive players will create avatars
to adventure in the Dungeon, conquer demons to empower
their avatars on their own. All growth in these avatars will
eventually be accumulated into Adam, a shared character
stored in the blockchain. In the battle of Dark Lord, the
player will use the shared Adam and one random character
summoned from the Last Trip to combat the Dark Lord, the
evil king created by the system. Each 30 times Dark Lord
is defeated in every chain, the battle of Blood Moon can be
triggered. The player will use the Adam in their corresponding
chain to conquer the Adams in other chains. According to the
recent publication [7], the Adam’s Venture and Last Trip are
using the same data set for avatars, which means the players
are generating contents for both games at the same time.
Crypto Space Commander40; Ethereum; 4/2019: Crypto
Space Commander (CSC) is a sandbox space MMO, that op-
erates a player-owned economy. Players can travel to different
star systems, mine planets for resources, craft items and ships
to sell, battle with pirates or other players while commanding
their unique spaceships. CSC utilizes the Ethereum blockchain
to secure game assets, enforce P2P contract actions, and run
the game economy. Almost everything can be crafted in the
CSC universe. In the beginning, players will be limited to
crafting modules, components, and spaceships. Future updates
will include the ability for players to craft space stations,
resource harvesters, and more. The CSC crafting system en-
courages players to make unique crafts by giving out rewards.
By focusing on their skills and efforts, players can create truly
valuable in-game items.
E. Summary: Game Categories
Fig. 2 summarized the classifications for the selected
blockchain games. Apparently, the technical limitations of
blockchain platforms may restrict the blockchain game design.
For example, Bitcoin is designed as a decentralized ledger, so
that it might not suitable for advanced blockchain applications.
On the other hand, Ethereum and EOS provide strong support
for smart contract execution, which allows them to implement
novel blockchain games. We believe that along with the
progress of the technologies, new blockchain platforms in
game vertical will be released to the market to further boost
this promising industry.
39http://aa.matrixDApp.com
40https://www.csc-game.com/
Fig. 2: Blockchain Game Categories
V. DATA ANALYS IS
To analyze the market trend of blockchain games, we
collected data up to 18/11/2018 of all 1,323 DApps running
on Ethereum, and top 30 EOS DApps which contributed
the majority of active users and transaction volume from
DAppRadar41. These DApps are divided into three categories:
1) Games: all kinds of blockchain games including Gam-
bling Games (e.g. online casinos), Collectible Games, and
Traditional Games (e.g. RPG, MMO, TCG, etc). 2) Trade
& Investment: including DApps relate to currency and busi-
ness, such as exchanges, auctions, marketplaces, and Ponzi
Schemes. 3) Others: including social networking software,
non-profit apps, protocols and so on. Two measure criteria
are used in the analysis: Weekly/Daily Active Users to
measure the popularity of certain categories of DApps. More
active users mean the DApp is more popular. Weekly/Daily
Transaction Volume to describe how much currency is trans-
acted through this category of DApps. It reflects the players’
willingness to pay.
A. DApps on Ethereum & EOS
1) DApps on Ethereum: The top sub-figure in Fig. 3 shows
that “Trade & Investment” DApps keep having most active
users, while its curve fluctuated sharply. “Games” had a
rapid rise in 11/2017, when the famous game CryptoKitties
was released. In a short period of time, players rushed into
CryptoKitties for novelty, but soon, a large part of them found
it did not meet their expectations and left. Hence, there is
a steep decline after the peak. Since then, the number of
weekly active users of games on Ethereum has been fluctuating
between 10k to 50k. “Others” category stay low because of
the small quantity of DApps in it. The bottom sub-figure
in Fig. 3 shows that “Trade & Investment” has dominating
transaction volume, but from 9/2018, it has a trend of falling.
41https://DAppradar.com/
For the “Games”, it has several rapid rises and falls. When
CryptoKitties released in 11/2017, the curve did not have an
enormous ascent, which implies a large group of CryptoKitties
players didn’t have the will of spending money, or they only
spent little ETH on this game. In conclusion, the transaction
volume of the “Games” category stays in a low condition. The
fluctuations didn’t significantly bring holistic growth.
Fig. 3: DApps on Ethereum
2) DApps on EOS: The top sub-figure in Fig. 4 shows that
the weekly active DApps user of all categories in EOS tend to
go up, especially for the “Games”, which has gone through an
exponential increase from 13/8/2018 this year and exceeded
“Others” after 8/10/2018. Meanwhile, The bottom sub-figure
in Fig. 4 shows the weekly transaction volume of “Games”
grew rapidly, while the other categories stayed low. Gambling
games contributed a lot to this result because casinos want
the real-time transaction to speed up the round of betting, and
EOS makes it possible.
Fig. 4: DApps on EOS
B. Games on Ethereum & EOS
1) Active User: Fig.5 depicts daily active users (DAU)
of Ethereum and EOS blockchain games from 11/2017 to
11/2018.
Fig. 5: Daily Active User of Blockchain Games
From the top sub-figure, we can see that the Ethereum’s
DAU once reached its peak of 14,211 on 9/12/2017. After
1/10/2018, the DAU of EOS tended to exceed Ethereum’s.
EOS curve once reached its local maximum on 3/11/2018,
23651 active users, in one day, and still has a rising trend. In
contrast, the Ethereum curve continues to stay low. This may
because of the faster transaction and free gas on EOS, which
make EOS a more suitable blockchain platform for games to
run on. The bottom sub-figure shows the proportion of daily
active users of games among all DApps. It is obvious that more
than 60% of DApp users nowadays are game players, which
implies the importance of games in the blockchain ecosystem.
Fig. 6: Daily Transaction Volume of Blockchain Games
2) Daily Transaction Volume: Fig. 6 shows that EOS has
an absolute advantage on transaction volume. Apart from
inflation: EOS is cheaper than ETH, one of the important
reasons is that zero gas fee attracted many gambling games and
a great number of gamblers, which greatly increases EOS’s
daily transaction volume. Fluctuations that almost vertical
could be pay-out of enormous prizes or bets pouring into the
jackpot.
C. Detailed Classified Games on Ethereum
Fig. 7: Games on Ethereum
Fig. 7 shows that the contribution of different categories in
games that supported the “Games” curve in the above section.
“Traditional Games” had most active users on average, while
the transaction wasn’t staying in high volume. “Gambling”
games had significant ascent in both daily active user and
transaction volume since 9/7/2018, a leading DApp appeared.
“Collectible” games stayed low at all time, can be explained
by they were bored and not suitable for investment.
D. Detailed Classified Games on EOS
The top sub-figure in Fig. 8 shows the weekly active user
of top 30 EOS games. Obviously, “Gambling” games player
are much more than “Traditional” games player. Considering
that there is a huge disparity between the number of DApps
in two categories, the average weekly active user number of
each category was calculated. The middle sub-figure of Fig. 8
shows that the active user number of “Traditional” Games far
exceeds “Gambling” games, which is because there is only
one game, EOS Knight42, in the top 30 DApps. It can be
deduced that if there are going to have more popular games
like EOS Knight appear on EOS, the “Traditional” Games will
have much more active users. The bottom sub-figure in Fig. 8
shows the weekly transaction Volume of Games on EOS. We
can see that “Gambling” games contributed the majority in
42https://eosknights.io/
Fig. 8: Games on EOS
total volume. “Traditional games” transaction was much lower,
indicating that players did not need to spend much money on
it. These games attracted real players and got rid of speculators
looking for profit.
E. Analysis Summary
From macro-perspective, each outstanding milestone DApp
can cause explosive user growth. However, the lack of sus-
tainability and consumer stickiness become a problem. This
sudden increment will go through a steep decline in a short
time. But after the reduction, the number of active users can
stabilize at a higher point compared to the value before the
surge. Blockchain game needs more leading products like
CryptoKitties or EOS Knight to drive the growth of the whole
industry and attract more public attention.
From micro-perspective, blockchain games should return to
games’ original intention: entertaining the players. However,
most blockchain games on the market now are still lack
of playability. This phenomenon can be explained from a
number of perspectives. First, the limitation of blockchain’s
functionality, which directly makes blockchain games lose
the ability to compete with fully functional traditional on-
line games. Second, over-emphasized financial characteristics.
Developers focus too much on implementing trading systems
or issuing tokens with blockchain. Seldom of them take
blockchain as an adjunct of games, or turn it into part of the
gameplay. Third, the blockchain game market is still in its
infancy. There has been no fierce market competition so far
as the traditional game market. Game engines like Unity and
Cocos are in an initial stage of integrating blockchain game
development packages. Till the end of 2018, no famous studio
or publisher has officially announced its entry into the public
chain game market or starting their own platform. These imply
that blockchain games have huge potential in the future.
VI. CONCLUSION AND VISION
Blockchain games benefit from the features of DApps:
non-fungible tokens and system transparency. Though these
games are still in their preliminary stage, the relationship
between players and game companies have been completely
changed through such a new concept. Blockchain games may
introduce new research directions in the following fields:
1) Game Technologies: new consensus models or alternative
technologies for blockchain games should be investigated, on
the purpose of improving players’ gaming experience with
blockchains; 2) Game Mechanics: new mechanics from the
idea of blockchain should be developed to enrich the gaming
contents. For example, recent work [7] has investigated the
possibility of asynchronous multi-player gaming experiences
across different games; 3) Narrative: the blockchain has in-
troduced a future of immutable data for the virtual world,
which may contribute the imagination of game narratives,
especially from the perspective of the immortality of life
and spirit. 4) Gamified Crowdsourcing: crowdsourcing is an
emerging technology that helps to harvest workforce from
crowd users. Traditional crowdsourcing platforms are facing
challenges like the malicious user, privacy leaks, high costs
and insufficient participants. Blockchain games provide a
perfect solution to these issues. First, blockchain [8] enables
anonymous, transparent and auditable incentive calculation
and distribution, while gamified crowdsourcing [9] may better
recruit those users who are insensitive to monetary incentives.
Overall, we believe that blockchain will become a disruptive
technology for the game industry. The blockchain-empowered
virtual worlds in games will eventually lead to real Utopias.
REFERENCES
[1] M. Nofer, P. Gomber, O. Hinz, and D. Schiereck, “Blockchain,” Business
& Information Systems Engineering, vol. 59, pp. 183–187, Jun 2017.
[2] S. Nakamoto, “Bitcoin: A peer-to-peer electronic cash system,” White
Paper: https://bitcoin.org/bitcoin.pdf, 2008.
[3] W. Cai, Z. Wang, J. B. Ernst, Z. Hong, C. Feng, and V. C. M.
Leung, “Decentralized applications: The blockchain-empowered software
system,” IEEE Access, vol. 6, pp. 53019–53033, 2018.
[4] V. Buterin, “Ethereum white paper: a next generation
smart contract & decentralized application platform,”
https://github.com/ethereum/wiki/wiki/White-Paper, 2013.
[5] B. K. Mohanta, S. S. Panda, and D. Jena, “An overview of smart contract
and use cases in blockchain technology,” in 2018 9th International
Conference on Computing, Communication and Networking Technologies
(ICCCNT), pp. 1–4, July 2018.
[6] A. Back, “Hashcash - a denial of service counter-measure,” 09 2002.
[7] W. Cai and X. Wu, “Demo abstract: An interoperable avatar framework
across multiple games and blockchains,” in 2019 IEEE Conference on
Computer Communications Demos (INFOCOM 2019 DEMOS), Paris,
France, April 29-May 2, 2019.
[8] R. Deng, J.-N. Liu, Y. Zhang, Y. Xiang, A. Yang, M. Li, L. Hou, J. Weng,
and W. Lu, “CrowdBC: A Blockchain-based Decentralized Framework for
Crowdsourcing,IEEE Transactions on Parallel and Distributed Systems,
pp. 1–1, 2018.
[9] B. Morschheuser, J. Hamari, J. Koivisto, and A. Maedche, “Gamified
crowdsourcing: Conceptualization, literature review, and future agenda,”
International Journal of Human-Computer Studies, vol. 106, pp. 26 – 43,
2017.
ResearchGate has not been able to resolve any citations for this publication.
Conference Paper
Full-text available
—In the last decade blockchain technology become mainstream research topic because of its decentralized, peer to peer transaction, distributed consensus, and anonymity properties. The blockchain technology overshadows regulatory problem and technical challenges. A smart contract is a set of programs which are self-verifying ,self-executing and tamper resistant. Smart contract with the integration of blockchain technology capable of doing a task in real time with low cost and provide a greater degree of security. This paper firstly, explains the various components and working principle of smart contract. Secondly, identify and analyse the various use cases of smart contract along with the advantage of using smart contract in blockchain application. Lastly, the paper concludes with challenges lie in implementing smart contract the future real-life scenario.
Article
Full-text available
Blockchain technology has attracted tremendous attention in both academia and capital market. However, overwhelming speculations on thousands of available cryptocurrencies and numerous initial coin offering (ICO) scams have also brought notorious debates on this emerging technology. This paper traces the development of blockchain systems to reveal the importance of decentralized applications (dApps) and the future value of blockchain.We survey the state-of-the-art dApps and discuss the direction of blockchain development to fulfill the desirable characteristics of dApps. The readers will gain an overview of dApp research and get familiar with recent developments in the blockchain.
Article
Full-text available
Two parallel phenomena are gaining attention in human-computer interaction research: gamification and crowdsourcing. Because crowdsourcing's success depends on a mass of motivated crowdsourcees, crowdsourcing platforms have increasingly been imbued with motivational design features borrowed from games; a practice often called gamification. While the body of literature and knowledge of the phenomenon have begun to accumulate, we still lack a comprehensive and systematic understanding of conceptual foundations, knowledge of how gamification is used in crowdsourcing, and whether it is effective. We first provide a conceptual framework for gamified crowdsourcing systems in order to understand and conceptualize the key aspects of the phenomenon. The paper's main contributions are derived through a systematic literature review that investigates how gamification has been examined in different types of crowdsourcing in a variety of domains. This meticulous mapping, which focuses on all aspects in our framework, enables us to infer what kinds of gamification efforts are effective in different crowdsourcing approaches as well as to point to a number of research gaps and lay out future research directions for gamified crowdsourcing systems. Overall, the results indicate that gamification has been an effective approach for increasing crowdsourcing participation and the quality of the crowdsourced work; however, differences exist between different types of crowdsourcing: the research conducted in the context of crowdsourcing of homogenous tasks has most commonly used simple gamification implementations, such as points and leaderboards, whereas crowdsourcing implementations that seek diverse and creative contributions employ gamification with a richer set of mechanics.
Article
Full-text available
Hashcash was originally proposed as a mechanism to throttle systematic abuse of un-metered internet resources such as email, and anonymous remailers in May 1997. Five years on, this paper captures in one place the various applications, improvements suggested and related subsequent publications, and describes initial experience from experiments using hashcash.
Conference Paper
Blockchain game is the most important category of decentralized applications. However, to leverage the feature of blockchain in state-of-the-art game mechanism design is still a challenge for developers and designers. In this work, we propose an interoperable blockchain gaming framework across multiple games and chains, to facilitate next-generation blockchain games. Two demo games are implemented to validate our framework.
Article
A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without going through a financial institution. Digital signatures provide part of the solution, but the main benefits are lost if a trusted third party is still required to prevent double-spending. We propose a solution to the double-spending problem using a peer-to-peer network. The network timestamps transactions by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work. The longest chain not only serves as proof of the sequence of events witnessed, but proof that it came from the largest pool of CPU power. As long as a majority of CPU power is controlled by nodes that are not cooperating to attack the network, they'll generate the longest chain and outpace attackers. The network itself requires minimal structure. Messages are broadcast on a best effort basis, and nodes can leave and rejoin the network at will, accepting the longest proof-of-work chain as proof of what happened while they were gone.
Ethereum white paper: a next generation smart contract & decentralized application platform
  • V Buterin
V. Buterin, "Ethereum white paper: a next generation smart contract & decentralized application platform," https://github.com/ethereum/wiki/wiki/White-Paper, 2013.