【Paper】

Exploring the game-of-chance elements in F2P mobile games- Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察―定性分析によるユーザーの感情に着目して―Koeder, Marco

Tanaka, Ema

Mitomo, Hitoshi

Graduate Student, GSAPS, Waseda University

Visiting Associate Professor

Professor, Waseda University

Free-to-play (F2P) mobile games are based on a business model which allows the majority of players to play the game for free
while only a small percentage (2-5%) is actually paying for the game (mostly through the purchase of virtual in-game items).
Monetization is done through so called micro-transactions within the game where players can acquire virtual items and tools. To
grow revenue and profit, game makers must motivate the limited amount of paying players to purchase more or to convert nonpayers into payer. This is done by combining an attractive game-play with settings/elements that entice players to make in-game
purchases. Especially, the above monetization mechanism could be boosted by the introduction of“game-of-chance”elements, orGacha in F2P mobile games in Japan. Gacha can lead to irrational overspending among some part of paying players since gamedevelopers deliberately (mis-)use its mechanics to increase their revenue and profit with these players.
This paper first outlines a basic framework of Gacha, its different mechanics and elements as well as its core issues basedon literature research and interview research on players and developers. A special focus is on the emotional involvementof paying players and on learning from game developers and game expert about the role of this involvement for revenue
generation. There are previous studies related to above F2P games but less focusing on its mechanism and its emotional
elements. Artful combination of game design and monetization is especially effective for Gacha which can be found in themost profitable F2P mobile games in Japan. The overall business model is questioned in terms of its sustainability a s
it depends on limited percentage of payers. This was also confirmed by several developers and analysts who werebeing interviewed.
Keywords: Gacha, freemium, mobile games, price discrimination, behavioral economics

1. Introduction *1even though the price is affected by chance depending onWith the increased penetration of smartphones, mobile

the setting of winning percentage by mobile game providers.

gaming apps have been on the rise globally. The mobile free-This is different from typical Western F2P games, where

to-play (F2P) games space accounts for the major revenue

virtual items can be purchased directly through in-gamewithin the global mobile apps economy. However, despite thecurrency with a fixed price. Japanese games often feature a

popularity of these games, only 2% of users actually make“Gacha”in the form of a refined lottery system where users

in-game purchases (Swerve, 2016). Within the global mobile

choose to pay for a chance to enter a real-time“lucky draw”

game market, Japan occupies a leading position in terms

to acquire these items (See Figure 1). In fact, the behavioralof revenues, generating $6.2 billion dollars in 2016 and in

impact of Gacha upon Japanese game players has been soterms of spending per player, where it ranks first in the world

significant, that several controversies have erupted between(SuperData Research, 2016). It has been suggested thatdevelopers, players and regulators in Japan because of its

one of the main drivers of revenues in the Japanese free-

perceived relationship to over-spending. The Japanese F2P

to-play mobile apps market is“Gacha”, a game-of-chancegame market and Gacha have been only briefly analyzed

based in-game payment mechanism. Gacha seems toin English-language academic literature. (Askeloef, 2013;

motivate players to spend more money in mobile F2P games.

Kanerva, 2015; Yamakami, 2012b, 2013a, 2013b, 2014;(Teramoto, Shibuya, & Akiyama, 2014). It means that

Shibuya & Teramoto, 2015).

payers of Gacha accept a kind of price discrimination in F2P

Figure 1: Difference between Western and Japanese F2P monetization: Adding the game-of-chance element to virtual item acquisition

DHU JOURNAL Vol.05 2018 ｜ 16

2. Research Question
From the game publisher side, it seems natural to adopt
Gacha as a mechanism for price discrimination allowing
them to maximize revenues for certain mobile game titles.
Gacha mechanisms work well and they are deeply intertwined
within Japanese mobile game design. From the user’s
perspective, however, how the game-of-chance element

regulated Gacha through the Law for Preventing Unjustifiable
Extras or Unexpected Benefit and Misleading Representation.
The law was enacted in 1962 to protect consumers frommisleading labeling of goods and services (CAA, 1962).

3.2. What is Gacha - a lottery system of virtual items
as prize / premiumin virtual environment affects users is not well investigated.

Lottery is common all over the world. Gacha, however, has

One key question here is why do some players pay more

several characteristics which are different from a real world

for Gacha drawing and others do not? From an Economics

lottery: low cost for the production and replication of prize

standpoint of view, the same virtual item obtainable by Gacha

items, flexibility of probability setting and a limited scope ofhas a different value for different players. To answer thisvalue restricted to the (in-game) online world. In the realquestion, this paper will depict the characteristics of Gacha

world, there are many kind of lotteries, from government-

based on Japanese mobile game market information andrun lotteries to marketing promotions which offer premium

related regulatory and self-regulatory measures for consumer

goods for winners, which are randomly selected from theprotection. Then this paper examines several analyticalparticipants. The real-world prize is more costly than virtualapproaches followed by the main part, which looks at players

goods. As the prizes are real goods, the probability ofand professionals insights and show issues and possibilities

winning is determined by the number of participants and prize

for further studies. In that sense, this paper is a preliminary

goods. In virtual world, a virtual item could be tremendously

one for further research on how Gacha elements, game-of-rare to obtain by setting the probability nearly zero. The

chance or artificial uncertainly to obtain virtual goods, affectvalue of a virtual item is generally contextual. For example, ausage and payment in freemium online services.

virtual game item is not usable in a different game no matter
how rare and“valuable”the item is.
Real world lottery and virtual world lotteries like Gacha also

3. Gacha as a game of chance element infreemium services
3.1. What is Gacha - gambling or lottery/lucky draw?

have similarities: The variety of offerings of chances to getitems. Both could be obtained through non-monetary andmonetary ways. And the winning possibility is largely determinedby the provider’s setting. Both are also often utilized as

According to previous studies, Gacha in online freemium

marketing promotion tools. Therefore, there are several

services seems similar to either gambling or lucky draws.

elements such as the selection of the winning prizes, probability

Shibuya describes Gacha as“…similar in screen appearance

to win and opportunity to participate in the lottery which affects

to vending machines that dispense children’s toys, andthe design of the mechanisms of a lottery. By combining theselucky players can win valuable gaming items this way…

elements, a variety of lotteries can be created.

Gacha can be played for free, however, extremely rare and/or valuable gaming items can also be obtained throughmonetary purchases of online Gacha products.”(Shibuya &Teramoto, 2015, p.3). Yamakami describes it as“Japanesegame vendors have made huge revenues using Gacha.
Gacha is a kind of gambling for special items.”(Yamakami,
2013a, p.268) and also as“ …a mechanism to provide arandomly picked item, sometimes free and sometimes as paid
items. Gacha is a great framework to introduce gambling
spirits into mobile social games. It also obscures the highprice to premium items because one attempt of Gacha canbe cheap.”(Yamakami, 2013b, p.738) or in more detail“Theprice is one or two dollars. Some of the contents come in aset, and therefore, users continue buying Gacha, trying theirluck at getting a full set (Yamakami, 2012a, p.1233).
Despite its similarity to gambling, Gacha could be

3.3. Elements and variation of Gacha in Japanese
mobile games
Looking at the literature, actual gameplay and mobile gameanalysis reports (Spicemart, 2016) Gacha can be seen as
being composed of the following points (Figure2):• It is a key game element and not the game itself (1)• It is paid for using an in-game virtual currency either bysoft or hard currency (real money) (2)• It is game-of-chance based including varied andadvanced chance mechanics and probabilities (3)• It uses elaborate audiovisual experiences during thedraw/revealing process (4)• It always provides a (virtual) reward (5)• Plays a role in the game (decorative, functional, social) (5a)understood as a lottery or lucky draw mechanism in a virtual• Available in different levels of rarity/limitedness (5b)world*1. Gambling is about betting money or valuable assets• Non-monetary (no real money trading) (5c)to get higher return than the betting amount. Gacha is about• Is often collectable (5d)pulling a lottery to get randomly allotted items. At gambling,• There are limited edition items that are often offeredplayer will lose when they get less than their bet. At Gacha
drawing, player will lose when they fail to get an item they
desired. Therefore, in this paper, we would like to understandGacha as kind of lottery mechanism. This is also in-line withthe regulatory perspective. The Japanese government had

17 ｜ DHU JOURNAL Vol.05 2018

during real time in-game events (5e)• It is only of value within the game and it is an essential
part of the game ecosystem (6)• It is mostly used to increase monetization for the gameprovider (7)【Paper】Exploring the game-of-chance elements in F2P mobile games - Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察― 定性分析によるユーザーの感情に着目して ―Figure 2: Outline of Gacha elements in Japanese mobile F2P games highlighting trigger points of emotional attachment

It needs to be mentioned there are several trigger points of•Consecutive Gacha: Purchasing Gacha in bulk increases

players emotions in there that help to increase the emotional

the overall probability of getting rare items (Figure 4).

state or emotional involvement of the player:•Open/Closed Gacha: A Gacha showing the probability of

The draw: The way the Gacha draw is presented/animated,acquiring a specific item.

the uncertain, chance based outcome of the draw using•Discounted Gacha: Special campaigns where users pay

advanced mechanics which will be covered later in thisless for a Gacha draw.

paper.

(Sources: Yamakami, 2012b; Teramoto, Shibuya, andThe reward: The draw will always result in winning a pricein the form of a virtual item. This item can help the player

Akiyama, 2014; Spicemart Report, 2016; Toto, 2016;
Interviews; Gameplay by authers)

to decorate/personalize his character, make it stronger andalso can serve for social functions in the game community.
Furthermore, it comes in different levels of rarity, can often
be collected and can be limited and the draw can be tied to
special time-limited in-game events where these items arebeing offered. All these components can affect the players
emotions and can trigger impulse, non-logical decision
making.
There are several Gacha mechanics which are being
used in Japanese mobile games. Our initial research in theliterature, in reports and games and through interviews haveshown over 10 different Gacha types/mechanics. Here is asmall overview of some of them.
•Kompu Gacha: Players need to acquire a set of items to
unlock a special rare item (Banned in 2012 because of
the issue of unknown probability).
•Box Gacha: Virtual box of set items with known
probabilities (Figure 3) .
•Sugoroku Gacha: Combining Gacha with a boardgame. A
Gacha acts like a dice which then allowed the player tomove on a board to unlock special items.
•Redraw Gacha: Users can do a redraw of a Gacha(sometimes for free, sometimes for a fee).

DHU JOURNAL Vol.05 2018 ｜ 18

Figure 3: Examples of Box Gacha Mechanics

Figure 4: Consecutive Gacha Mechanics

4. How Gacha became controversial and (self-)
regulated in Japan

4.2. Self-regulation: Through probability guidelines

4.1. Government Regulation: Kompu-Gacha casethis time associated with a specific game (Grandblue Fantasy,

Despite the fact that Gacha has existed in mobile games
in Japan since around 2004 with one of the first games
being Maple Story. (4Gamer 2007), complaints to theConsumer Agency in Japan had increased in 2011 (Machida,2012). The main issue was the so-called mechanics of“KompuGacha” which had been previously mentioned in
the paper. The name comes from the word KOMPURETO
in Japanese which means “to complete”. This mechanicrequires the player to first collect a series of items (completeset) before being able to unlock a specific, rare item withouta clear outline of winning probabilities. The Consumer
Affairs Agency in Japan (CAA) banned the practice of“KompuGacha” in 2012 for the reason, that it corrupts

Then in 2015 another Gacha related issue became public,
for example) and its lack of providing correct probabilities/
costs for acquiring specific items (Nakajima, 2016). Asa reaction to this, the Association of Japanese gamedevelopers (CESA) issued a guideline in 2016 asking theirmembers to provide more transparency for Gacha mechanics
within their games. The guidelines require game makers to
implement one of the following 4 standards:(a) The limit on the estimated price (the price calculated
as an expected value according to the set distributionrate) to obtain any rare Gacha item should be within
100 times the price of a single paid Gacha, and in thecase that this limit is exceeded, that estimated priceor its multiplying factor needs to be displayed on the
Gacha page.

the game experience as the system makes it difficult to(b) The estimated price limit to obtain any rare Gacha item

understand the probability to win a prize (CAA, 2012). Game

should be within 50,000 yen, and in the case thatcompanies had to abandon these mechanics and switched tothis limit is exceeded, that estimated price needs to beother kind of Gacha or invented new ones. Over the courseof time game developers introduced several new Gacha
mechanics (for example the above “Box Gacha”), severalof them with hidden probabilities and hidden total costs foracquisition by just hinting how rare some items are.

displayed on the Gacha page.
(c) The upper limit and lower limit of distribution rates forrare Gacha items are to be displayed.
(d) The distribution rates for each type of rare Gacha item
are to be displayed.
(Spicemart 2016, p.6)
CESA member game companies only had to fulfill one of above
conditions since it did not require to adhere to of all of them.

19 ｜ DHU JOURNAL Vol.05 2018

【Paper】Exploring the game-of-chance elements in F2P mobile games - Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察

5 Analytical Framework consideration
5.1. Previously applied frameworks in the virtual
item / F2P context
In the field of (Western) Free-to-play games and virtual item
purchase several analytical frameworks have been appliedso far in studies. The most frequent being the Technology
Acceptance Model (Davis, 1989; Davis, Bagozzi, & Warshaw,
1989) which can be found in several studies on virtual item
purchases (Mäntymäki, Salo, 2011; Shin, 2008; Cheon,
2013;Hsu, 2004) and the Unified Theory of Acceptance and― 定性分析によるユーザーの感情に着目して ―makes a virtual item more attractive for players. Additionally,
the probability of Gacha for obtaining a certain rare item is
not static but changeable by the game providers. During so
called“real-time events”game providers offer an increased
probability of obtaining specific rare items or introduce
limited edition items for this event. How this kind of artificial
probability and rarity could affect users needs more analysis
as serious research has just started for its short history.
How Gacha is perceived by players and game professionals
provides another interesting opportunity to look at the topic.

Use of Technology (Venkatesh, Morris, Davis & Davis, 2003)
which had also been utilized for virtual world and virtual
item purchases (Mäntymäki, & Salo, 2013; Guo, & Barnes,

6. Gacha perception by users and developers

2011; Guo, Barnes, 2012) followed by papers applying a

To learn more about the underlying emotional elements

value based theory framework. (Han & Windsor, 2013; Kim,

related to F2P games and Gacha, interviews with players as

Gupta, & Koh, 2011; Park, & Lee, 2011).

well as game industry professionals had been conducted.

The role and function of virtual items have been outlined by

In previous studies, interviews with Japanese mobile F2P

several authors such as Lin and Sun talking about their roles

players and professionals in English academic literature are

as functional tools and decorative tools (Lin, & Sun, 2007)

still rare. (For example, in the thesis by Askeloef, 2013;or Lehdonvirta dividing them into separate categories based

Kanerva, 2015)

on functional, emotional, and social attributes (Lehdonvirta,2009).
Virtual items and virtual worlds have also been studied
recently more from an economic perspective leading to
the concept of virtual economies put forward mainly byCastronova and Lehdonvirta. According to them a virtual
economy can be analyzed similar to a real economy. Users
treat virtual goods and virtual money similar to real goods
and real money (Lehdonvirta, & Castronova, 2014).
Yet these above studies have not covered Gacha and its
possible effects because research has been mostly focusedon Western game titles.

5.2. Behavioral economics and probability weighting
function

6.1 Methodology
To achieve a better understanding of the above andto unearth more in-depth insights, the authors applied aqualitative approach using semi-structured interviews. Thisdecision was shaped by the following antecedents:
1) In F2P games only around 2% of players pay for virtual
items according to a study of Swrve (Swrve, 2016).
This makes it very costly and time intensive to collectquantitative survey insights from paying players.
2) Quantitative methods sometimes do not allow an insight
into deeper issues and it is necessary to take a more
explorative approach (Schensul, Schensul, & LeCompte,
1999; Bernard, 2017; Harrell, & Bradley, 2009). Whenit comes to F2P, recent research has pointed out that

One of interesting theoretical angles comes from Behavioral

quantitative surveys among F2P players on in-game items

Economics on lottery analysis. The topic of Behavioral(re)-purchase do not always reflect their true intentions

Economics bias elements and how they might impact (mobile)and motives well. Instead researchers should look more

Free-to-play-games have already been briefly outlined byinto actual game data and unconscious motives (LeeHamari (Hamari, 2011) and have been discussed for theat al., 2015).

games/mobile app environment (Paavilainen et al., 2013;

3) Game companies are rather reluctant to share their

Reiners & Wood, 2015; Stockinger et al., 2015; Heimo,game data with outside parties because this data isHarviainen, Kimppa, et al., 2016; Zagal et al. 2013). As

most valuable to them for their monetization and they

these thoughts are based on Western games, they did not

do not want competitors to know about their data

look at Gacha game-of-chance elements. On the other hand,(Sifa, Drachen, & Bauckhage, 2018).

Behavioral Economics have shown that game-of-chance/4) The authors wanted to also learn more about thelottery elements in general can help change or enforce a

professional’s perspective. While looking at the limited

behavior better than fixed incentives (Kearney, Tufano et al,

F2P research literature they found that a qualitative

2010; Kimmel, Troxel et al, 2012; Goette, Stutzer, 2008;

interview approach has already had been successfully

Nvqvist, Corno, et al. 2015; Volpp, Troxel, et al. 2008) .

used for understanding Western players as well as

Basically, Behavioral Economics explains the reason oflottery buying through the “probability weighting function”

game developers insights (Paavilainen et al., 2013;
Alha, Paavilainen, Hamari, Kinnunen, & 2014).

(Gonzalez, & Wu, 1999). Game players might be less inclined

After talks with one game industry analyst and two

to pay for acquiring specific items or content when they areplayers the authors developed two semi-structured interview

associated with Gacha mechanisms rather than a fixed price.

guidelines. One for player and one for game industry

Gacha, however, is different from lottery as payers seem toprofessionals. The interview length was set to 60-90 minutes

value rarity or collectability of the virtual items itself which

for each participant. Because of privacy concerns the

could be obtained by Gacha and not an actual monetaryinterviews were not recorded and instead the interviewers

value it represents. Gachas have a rarity element which

took notes during the session and the names were replaced

DHU JOURNAL Vol.05 2018 ｜ 20

by initials in this paper. The subject was asked if he or she

in Japanese and 4 in English. 6 were identified as casual

was comfortable to do the interview in English. If not thegamers and 4 as hardcore gamers. All interviews wereinterview was done in Japanese and English notes wereconducted face to face (Chart 1, Chart2).

taken and then reconfirmed with the subject in Japanese.

The player interviews were structured into 5 main sections.

If possible, interviews were done face-to-face. As the goal

The first section explained about the overall research goalsof the interviews was to unveil more in depth insights into

to make the participants understand the setting. The second

players and professionals thinking and perspective, the overall

section focused on collecting basic demographic data andframework of the questions was supposed to be used in athen in the third section the players were asked in an open

flexible manner to allow respondents to express themselvessetting about their past gaming experiences including mobile

freely and to also touch upon topics mentioned by them thatgames and their game preferences, to build rapport and towere not part of the questions but were seen as valuable inlearn more about their gaming behavior. After that the in the

discovering new findings. The interviews were conducted

fourth section the interviewer focused more on their mobile

over a period of 24 months from April 2016 - April 2018.

gaming and Gacha experiences including what games they

The authors tried to replicate the gender distribution ofplay, where they play, why they play as well as how theysmartphone players in Japan by including an equal amountfound out about the game and how they got into that game.

of male and female players. According to a study by Sega

Based on the games they play or have played the questions

51.9% of smartphone players are male and 48.1% arethen focused on their experience with Gacha and paid Gacha

female (Sega, 2017). Players were recruited through theas well as their emotional attachments to the games and toauthors personal networks as well as through social media

Gacha. This also included their very personal thoughts about

and online game forums with the goal to identify F2P players

Gacha in general, why they purchase Gacha and when/in

who had experience in playing Gacha games and have had

what setting they purchased it. The interview then closed

experience in paying for Gacha. In total 10 players werewith the fifth section asking the participants if they had any

interviewed. Out of them 9 had experience with paying

other thought or comments to add.

for Gacha. Interviews for 6 interviewees were conducted

Chart 1: List of interviewees of players and basic attributes (anonymized) with interview date
Name

GenderAgeInterview done in

Company

Profession

Interview Type

Date

Player Type

I.Y.

Male

52

Japanese

Ad Agency

Planner

F2F

1/10/17

Gamer

Y.K.

Male

31

Japanese

Event Planning

Client Services

F2F

11/16/16

Casual Player

T.I.

Male

25

EnglishIT Services

PR Department

F2F

11/10/17

Gamer

M.T.

Male

50

Japanese

AgencyPlanner

F2F

8/10/17

Casual Player

C.K.

Female41

EnglishHealth Company

Client Services

F2F

10/25/17

Casual Player

M.S.

Female38

EnglishIT company

Planner

F2F

9/20/17

Casual Player

M.W.

Female36

EnglishHealth Services

Counsellor

F2F

2/5/17

Gamer

S.I.

Male

35

Japanese

Production House

Planner

F2F

7/19/17

Casual Player

M.A.

Male

36

Japanese

IT company

Client Services

F2F

3/4/18

Gamer

C.W.

Female31

Japanese

Beauty Company

Director

F2F

2/5/18Casual Player*F2F:Face to Face

Chart 2: List of interviewees of game professional and basic attributes (anonymized) with interview date
Name

GenderAgeInterview done in

Company

Profession

Interview Type

Date

Y.O.

Male

37

Japanese

Mobile Game Analysis Company

Game Market Business Analyst

F2F

5/4/16

C.T.

Male

32

EnglishMobile Game Developer

F2P Game Developer

F2F

11/6/17

Y.A.

Male

35

Japanese

Mobile Game Developer

F2P Game Developer

F2F

11/10/16

G.K.

Male

37

EnglishMobile Game Developer

F2P Game Developer/PlannerSkype

12/2/16

S.T.

Male

42

EnglishF2P Game Analysis Company

Game Analyst

F2F

5/28/16

K.N.

Male

39

EnglishJapanese Newspaper

Game Journalist

F2F

11/21/17

J.D.

Male

52

EnglishFinancial Analysis Company

Game Industry Analyst

F2F

7/31/18

21 ｜ DHU JOURNAL Vol.05 2018

【Paper】Exploring the game-of-chance elements in F2P mobile games - Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察― 定性分析によるユーザーの感情に着目して ―Also, Japan market game industry professionals werespend more money on acquiring these items. If the chances

selected through looking at online articles, research reports

to acquire these rare items increased during special eventsand blog entries published by them or about them. The

he was more willing to invest his money into it because of

focus here was on their expertise in F2P games and Gacha.

the increased chance of acquiring them.

The authors then reached out to them explaining about the

A 50 year old male player who used to spend aroundresearch and asking for an interview. 10 professionals were

50,000 yen a month on Gacha pointed out that he got into

contacted and 6 initially agreed to be interviewed. Four ofa specific game because of the characters featured in there.

the interviews were conducted in English and 2 interviews

There was also an Anime series with these characters and hewere conducted in Japanese. Except for one interview all

started watching it and purchased also several merchandise

were conducted face-to-face. An additional industry expert

articles. His main motivation for Gacha purchase was tointerview had been conducted in July 2018 after receiving aacquire new limited-edition outfits for the in-game characters.

belated positive agreement for an interview.

For him this experience was very emotional making it

The professional interviews were structured into 5 sections.

sometimes hard to control his spending.

The first section explained about the overall research, theA female player in her early 40s who mostly played casual

second section asked for basic demographic data. The third

F2P titles mentioned she did not like it when games makesection asked about the persons past career up to now for

players wait until they pay to be able to move forward in therapport building and to learn more about their roles andgame. The game she played were introduced to her throughexperiences. In the fourth section the interviewers tried toher friends and colleagues. She sometimes pays for Gacha

have an open talk about the professional’s exposure toto get limited edition items and characters but she is worried

Gacha in their career, their thought on the role of Gacha

about overspending and getting into financial troubles.

in monetization in Japan, issues they see, if possible a

The worry of spending too much was also brought up bycomparison to other markets in Asia and the West, and theiranother 36 year old female player. Her worry was that sheoutlook of Gacha in general. The fifth section then asked

would get into a game too much and become too attachedabout any additional insight they would like to share that had

and then ends up spending more than she can afford. In her

not been covered in the previous discussion.

case she was playing a more casual F2P game and a more
complex F2P RPG game. The spending on the RPG game

6.2 Player Insights
An insightful interview was with a 52 years old Japanesemale player who, according to this own statement, waswas, what she was worried about, as she mentioned it keeps
her much more emotional involved and attached and shecannot trust herself anymore in such a state.

spending over 100,000 Yen per month on Gacha in mobile

Another male player in his mid 30s who was also a big fan

games. When asked why he is spending this amountof mobile F2P RPGs stated that he stopped playing a specificof money he mentioned that Gacha is a self-rewarding

game because of time restraints but also because he heard

experience for him that helps him to unwind and thatin the news about the game company behind the game

he would feel less excited about Gacha if it was free oftelling lies to players about the chances of acquiring specificcharge. He does not care about looking at the probability

rare item. He felt cheated by that company and felt they hadof acquiring a specific item yet he is acquiring most of the

been tinkering with his enjoyment and love for the game.

paid Gacha during real-time events when the game offers

Furthermore another male player in his 30s talked about

increased probability and/or special limited items. But hehis worry about F2P games in general. He always needs toalso mentioned that he is becoming tired of Gacha as hebe online to play. There are so many F2P games out there.

proceeds in the game and acquires rare items as there is notSome are gone after less than a year. He is worried about

so much to look forward to anymore.

losing all his achievements and items he paid for once a

On the contrary, a 31 years old male player pointed out

game is no longer popular and the game servers were shutthat he is not willing to pay for Gacha. He saw Gacha as adown. He was worried the game provider would let him down.

tool to try and challenge his own luck and he gets excited

7 out of the 10 players interviewed were introduced toabout the upcoming result and it makes him feel good to

the game they played through their friends. Game progressacquire a rare item by chance. If he was to pay for it heand achievements were a popular discussion topic for them.

wanted to know the chance of winning specific items to make

Especially for the male players

sure if it is worth it or not.

8 out of the 10 players interviewed stated “rarity” andIn an interview with a 25-year-old male player he pointed

a temporal increased winning probability during special

out that for him one of the key attraction points of items

campaigns as their key motivators for paying for Gacha.

he can acquire through Gacha is their rarity and the fact

When being asked what increased probability means for themthat some of them are only available for a limited amountthey mentioned they“feel”their chance of winning will beof time. Owning a (virtual) item that is rare and only a few

higher, they will be double or triple but none of them wasother people have, was seen as a valuable asset for him. He

talking about any percentages.

also stated that for him this was one important motivation to

DHU JOURNAL Vol.05 2018 ｜ 22

6.3 Professionals Insight
According to a 37 years old Game Market Business
Analyst, Gacha is used mainly for increasing the spending ofplayers. He also brought up the fact that around 90% of
Gacha purchases happen during the beginning of the monthas this is when people get their salary.

the few paying players and the different Gacha mechanics

When the discussion came to recent regulations and ways

and frequent new (rare) item content combined with in-

how to improve monetization one former developer mentioned

game real time events help to increase the spending. Playersthat currently game maker have become very careful about

enjoy the “luck” moment of the Gacha draw, which is aplaying around with probabilities or new types of Gacha

different emotional experience from simply paying for an item.

mechanics. Instead they are focusing on developing a

Developers are becoming more creative about inventing new

broader variety of rare items as well as limited edition items

item designs to increase their sales. But also it is importantand offer them through in-game campaigns. According to him

to be more clear about the cost and/or chances of acquiring

this was seen as a very profitable approach as the demand

items in the future to not upset players.

for these items is high and players are willing to invest more

A 32 years old former F2P Game Developer emphasizedto acquire them.

that Gacha, game design and payment are closely intertwined

Another F2P developer mentioned that without Gacha

and cannot be separated. He called it‘The holy trinity’of

players would not see the game as entertaining. Playing a

F2P game design in Japan”.

Gacha creates an extra level of sensation and of high stakes.

He also stressed that Japanese players want Gacha in theirThis is something very emotional and has nothing to do with

games as an extra level of entertainment. Without the Gacha

any logical process. It is more like a skinner box. So showing

element, item acquisition would lose its attractiveness. A 35

the odds of wining items does not matter to players. He also

years old former Mobage Developer supported this statement

said he thinks they cannot understand what a probability ofmentioning that without Gacha players would not see it as

0.001% means. He compared it to buying a lottery ticket.

entertaining.

The buyer thinks of winning the lottery but not about the

Furthermore he pointed out that many Japanese gamedevelopers got addicted to making quick money with Gacha

chance of winning it. Similar to this several Gacha payers arein for the thrill of winning.

in the past. Back in the early days the main devices wereA F2P Game Analyst pointed out that in Japan Gacha

feature phones and the game developers also owned theis a purely money-making phenomenon. Companies try toplatforms. Making money with F2P games was easy andcome up with many ways and mechanics to get more money

cheap. But with the success of smartphones the situationfrom the paying players.

had changed. Game development costs have increased

specific game it is easy to make him pay again and again.

drastically, and developers need to give away 30% of their

The developers come up with new items, special purchaserevenue to Google or Apple. So some developers feel they

events. They have a clear picture of what is needed to makewant to get their money back and start to look for many

players buy more. Often the player is not aware how muchnew ways to increase the spending of players and increase

he needs to spend to get some especially rare goods. This

their own profits. Sometimes these practices can become

lead to several issue and government had to intervene. But

dangerous and hurt the player and also the game developer.

according to him not much had changed. Yet Gacha only

The social element is also important for monetizing Gacha.

works if the game design, character design and story isPeer pressure can motivate others to pay for Gacha and to

good. If players stop enjoying, they stop playing.

aquire unique items others already got.

Once a player is hooked on a

Talking to a Japanese game journalist he mentioned that

Another F2P game designers in his late 30s stressed

the gambling aspect is the key attraction behind Gacha.

that Gacha takes a lot of hints from Pachinko (a popular

People can feel excited about it but game makers take too

Japanese Slot-Machine variant). He mentioned that lights

much advantage of it. Gacha can be very frustrating if players

and other mechanics that announce something will happen

want to get an item but cannot get it. Youtubers in Japan

are important including exciting animations before special

often take videos of their desperate attempts. This is also

results. He pointed out that the top monetizing games

what lead to the GrandBlue scandal. To get a rare characterfeature very elaborate Gacha animations. Visual feedback

or item chance is only about 1%. The bad fact is thatand visual experience is important to players. He explained,

players could pay an unlimited amount of money. With Gacha

that Gacha animations are usually for heavy spenders only.

being more like a challenge of luck it can create addition

Also, if players purchase Consecutive Gacha (for example 10

friction in players leading to overspending. According to

Gacha in a row) the Gacha animation is also different.

him, paid Gacha is an unhealthy business model and should

According to him Japan was the first country in the world tobe replaced with other business models. He suggested adevelop the concept of Games as“Software as a Service”.

monthly subscription model for F2P games but he feels game

Games are built to last for about 2-3 years and so called

companies are too greedy to do this. He also plead that“gates”are built into the core concept of these games as

there should be a spending cap on games per month.

artificial borders for players to drive monetization. In the

A recent interview with a financial analyst for the gameend it is about collecting as much money as possible fromindustry added some extra insights. He stated that most F2P

23 ｜ DHU JOURNAL Vol.05 2018

【Paper】Exploring the game-of-chance elements in F2P mobile games - Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察― 定性分析によるユーザーの感情に着目して ―players who use Gacha do not pay for it. They use“free”

a value within the game ecosystem. Similar to real lotteries

Gacha draws. He also explained about Japanese Gacha

there are free and paid options and the provider sets thegames abroad. According to him many Japanese Gacha

probability of winning and the range of items to be won.

games have failed abroad. Only some are successful. The

Because of its virtuality it is possible to develop andones who are successful are the ones who have a goodexperiment with many different types of Gacha mechanics

balance between game play and payment. If the game isas well as changing rarities to help increase the games

focusing too much on paywalls and making players pay tomonetization. Some of them without providing any probability

get ahead in the game it’s not fun anymore The game-of-of winning/acquiring a specific item.

chance element adds another barrier for players. But if the

These mechanics have led to issues and intervention fromgame itself is entertaining then this barrier can activate someregulators. In terms of regulation for Gacha, Japan moved

players who are prone and weak for gambling like experiencefrom regulatory to self-regulatory activities.

and help with increasing the overall games revenue with them.

Japanese game developers and analysts see Gacha asa fundamental element of Free-to-Play mobile games in

6.4 Findings from Interviews

the market, helping to monetize these games and there

We can see that for paying players rare and limited-edition

are players who spend considerable amounts of money foritems, collectability combined with campaigns and events has

Gacha. The elements of rarity, limited time offers and change

an impact on their Gacha purchasing behavior. Also Gacha

of probability help with the monetization.

seems to be an extra emotional experience for them to test

There are already several frameworks which have been

their luck. Further more their social peers play a role in what

applied to virtual items, F2P games and virtual worlds. Gacha

game they play, how long they play it and if they invest in

has not been considered in these studies. In the F2P gamepaid Gacha or not. But at the same time the game itself, its

context Behavioral Economics has been briefly discussed

design, content and their emotional attachment to it appears

to help explain some of the behaviors of players. Given theto be a key shaping factor in their commitment to invest timelottery mechanics of Gacha, applying Behavioral Economics

and money into a game. Some players are worried about not

can add a new angle to the discussion.

being able to control their spending and some felt remorse
about overspending.

This paper found from qualitative analysis that theemotional attachment some players have to paid Gacha can

From the professional perspective it seems like developers

be seen as problematic and these attachments are being

are very well aware of the emotional impact Gacha has on

artificially nurtured and intensified by the game developer

paying players. The desire to increase profits lets developers

for profit optimization (Figure 5). These issues seem to beexperiment with many new limited edition items and elaborate

inherent to the current major F2P monetization model. While

animations to hook players into paying. One developer

it can be seen as a “good game design” to emotionallyeven called Gacha an elaborate skinner box used by gameengage and motivate players to keep playing a specific gamecompanies to increase individual payments.

title, exploiting this engagement for monetization by using

A l s o anal ys ts s eem to b e worri ed ab out the futuresustainability of the business model. Short term profit games

game-of-chance mechanics can be seen as controversial or
as a“bad game design”.

might scare away players in the long term. So striking a goodbalance between monetization desires and gameplay can bea key factor of long term success.

7. Summary
Free-to-play (F2P) mobile games are based on a businessmodel which allows the majority of players to play the gamefor free while only a small percentage (2-5%) is actually
paying for the game (mostly through the purchase of virtualin-game items). This requires the game providers to focus on
the monetization of a small group of users.
Gacha -as a special game-of-chance based purchase ofvirtual in-game items- has been outlined as one of the key
drivers for this monetization in Japan. While some Gacha
draws do not require the payment of real money, some do.
In the eyes of several Japanese researchers Gacha can beseen as a virtual lottery system. Different from a real lottery,it offers a flexible probability, (virtual) prizes items can be
expanded and reproduced at very low costs and only have

DHU JOURNAL Vol.05 2018 ｜ 24

Figure 5: On emotional elements of Gacha and game design:
Gacha creates an extra level of emotionalizing purchase for virtual items in F2P games for some part of players.

8. Further analysis and discussion
This paper just gives a preliminary overview of Gacha andthe different angles involved from the Gacha mechanics sideand its uncertainty element, the regulatory side, developers

a turn. The sound of the turning lever is like“Gacha Gacha”andthe sound of opening a capsule is similar to“Pon”thus giving
it its name“Gacha Pon”. Generally, Gacha Gacha toys cannotbought anywhere else but through the Gacha Pon machine.
Therefore, people who want a Gacha Gacha toy have to try theirside and players side and how Gacha could affect freemiumluck by paying real money and then turning the Gacha Gacha

online services.

machine lever.

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27 ｜ DHU JOURNAL Vol.05 2018

【Paper】Exploring the game-of-chance elements in F2P mobile games - Insights of player's emotions from qualitative analysis フリーミアム型モバイル・ゲームの確率変動要素の考察― 定性分析によるユーザーの感情に着目して ―【論文】

フリーミアム型モバイル・ゲームの確率変動要素の考察―定性分析によるユーザーの感情に着目して―マルコ・クーダー 1・田中 絵麻 2・三友 仁志 3
（1 博士候補生, 早稲田大学大学院アジア太平洋研究科・2 客員准教授, デジタルハリウッド大学大学院・3 教授, 早稲田大学大学院アジア太平洋研究科）
無料プレイ（Free to play: F2P）のビジネスモデルを採用するモバイル・ゲームでは、ごく一部の利用者（ユーザーの 2 ～ 5% 程度）が課金している（そのうち、多くの場合がアイテム課金である）。モバイル・ゲームの収益は、マイクロトランザクションと呼ばれるプレイヤーによるゲーム内での仮想アイテムや機能の購入（この購入行為はプレイヤー側からもゲーム開発者側も「課金／課金する」と呼ばれる）により発生する。収益拡大のためには、限られた人数のプレイヤーがより課金するか、もしくは、非課金者に課金させるかの方法がある。そのため、より魅力的なゲーム・プレイ経験と、ゲーム内課金へとプレイヤーを誘導する要素を接合することが行われている。特に、収益化メカニズムは、日本の F2P モバイル・
ゲームにおいて「ガチャ」と呼ばれるくじ要素の導入によって強化されうるものである。ゲーム開発者が収益を拡大するため、意図的にガチャのメカニズムを利用し、一部のプレイヤーの非合理的な支払い過多の状態を引き起こしている。
そこで、本論では、文献調査とインタビュー調査から、最初に、F2P のモバイル・ゲームにおける確率変動要素である「ガチャ」の基本的な枠組み、さまざまなメカニズムと要素、主な課題を概観した。中でも、プレイヤーとゲーム開発者や専門家へのインタビューから、課金プレイヤーの感情的な没入に注目し、この没入が収益化において役割を果たしていることを明らかにした。F2P にかかる先行研究では、メカニズムや感情要素に着目したものは少ない。多くの収益性の高い日本の F2P ゲームにおいて、ガチャと呼ばれる巧妙なゲーム設計と収益化の組み合わせが効果的に用いられているといえる。一方で、このビジネスモデルは、一部の課金者に依存するという意味で持続可能性が疑問視されている。このことは、ゲーム開発者やアナリストへのインタビューでも指摘された。
キーワード：ガチャ、フリーミアム、モバイル・ゲーム、価格差別、行動経済学

DHU JOURNAL Vol.05 2018 ｜ 28