Utolypse

How Interactive Visual Hints Help Players Solve In-Game Puzzles

Thesis Draft

By

Yu Xiao

To

The College of Arts, Media and Design

In Partial Fulfillment of the Requirements for the Degree of Master of Science in Game Science and Design

Advisor: Celia Pearce

Northeastern University Boston, Massachusetts

December 2018

TABLE OF CONTENTS

Abstract 2

1. Introduction 3

2. Background 3

3. Game Design 9

4. Game Research 17

5. Results 19

6. Conclusion 23

7. Discussion 24

8. Appendix 25

Reference 26

1

ABSTRACT

The main purpose of the thesis research is finding out how the interactive visual hints

help players solve the in-game puzzles. In order to test this design problem, I and another

GSND student Zhihui Chang created a game Utolypse. This paper provides a brief

overview of the game, Utolypse's design process, including the design of the game's

mechanisms, dynamics, and aesthetics, as well as the design of each puzzle in the game.

In order to learn how hints will help players solve the in-game puzzle, an A/B test was

selected as the main experimental method. During the experiment, participants were

randomly divided into two groups. One group played the game with hints, and one without.

By comparing the time the player uses to solve single puzzle, we found that with hints,

players can better improve their game strategies in playing the game, so as to more

effectively master the game.

Keywords: Puzzle game, Game design, Visual design, Interaction, A/B test

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1. Introduction

Video games have different design considerations and usability issues than other

types of software. The ISO 9241-11 definition of usability includes three independent

measures including efficiency, effectiveness, and satisfaction. In the case of video game

usability, effectiveness and efficiency are secondary considerations in relation to satisfaction

(Federoff, 2002).

Utolypse, is a PC based puzzle game, which requires players to use the camera to

adjust the angle to solve the puzzles. When designing the game, we focused on how to satisfy

players by offering a superior game experience. The core mechanic of puzzle game is that

players should take use of the existed function and information to solve the puzzle and

achieve goals. In puzzle game design, the information almost equals to hints. Generally,

game should give hints, but not too many (Clanton, 1998). Therefore, the way of giving

players information becomes an important indicator for judging whether the game is

satisfactory to the player.

Games deliver messages to the user in an unobtrusive way that does not require users

to dismiss, acknowledge, or address those messages. Games have shown that reducing

demands on the user’s attention can aid performance; through the use of sound, speech,

transient text, and animation, games communicate in a calm manner that promotes a fluid,

uninterrupted workflow (Dyck, Pinelle, Brown, & Gutwin, 2003). In order to find out the

best way to give players hints, game designers need to know how most existing games give

players hints. There are several ways that are used in giving hints in puzzle game: context

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hint, image hint, pattern hint, resource hnt and mechanic hint (Murphy, 2011). Giving

context and image as hints is much more easier for players to get information, because the

brain can get more useful information from the context through experience, and the brain

processes the image 6000 times faster than the context (Blacker & Curby, 2013). Pattern is

similar to a mathematical way, it needs players to have a certain classification and summary

ability to find a way to solve the problem. Resource is about trial and error. And the

Mechanic Hint, such as Monument Valley (USTWO, 2014) is more about giving players an

overall understanding of how to play the game and build up their own strategies.

The player will spontaneously apply the previously acquired information to the

following game, especially the information the player gets during the interaction (Blacker &

Curby, 2013). So the game takes use of the most general way of hints design, mechanic hint,

and efficient way of hints design, image hint to build up the Puzzle 4&5. For these two

puzzles, players need to solve an image based puzzle first, and then use this image to solve

the next puzzle. Of course, players won’t be told that there is a specific relationship between

these two puzzles but will only discover this through gameplay.

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2. Background

Different Approaches to Hints Design The puzzle game means that the puzzle will be solved. This ultimate purpose requests

game designers to balance puzzle design and giving hints. In Greek mythology, Hera Sphinx

sits on a cliff near the city of Chapel, stopping passers-by and asking them the riddles taught

by Muse. Those who cannot answer the riddle will suffer a fate typical in such mythological

stories, as they are killed and eaten. One riddle is: "Which animal walks with four legs in the

morning, walks with two legs at noon, walks with three legs at night? When the legs are the

most, it is also the time when he walks the slowest and has the weakest physical strength."

Oedipus gave the correct answer which is the "person". Sphinx was ashamed and was killed

by Oedipus (Janice Siegel, 2005).

This myth reveals the basic structure of the puzzle game: starting with a goal and

encountering the obstacle that has to be broken. The obstacle has a unique solution, trying to

find this unique solution, constantly breaking these obstacles to solve the puzzles and

eventually accomplish their goals in this world. This is the basic prototype of the puzzle

game. It’s not only the structure of the puzzle games, but also everyone’s life structure.

That’s why games with high-quality metaphors and hints are more fascinating.

Gorogoa is an elegant evolution of the puzzle genre. It uses the graphics in the

painting (Figure 1) as the interactive object. By using a large number of familiar art elements

to activate the impressions associated with the player's knowledge structure, Gorogoa gives

the player a emotionally rich experience of the world. In the game, players can discover

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hidden hints through interactive elements in the screen. Gorogoa flexibly uses the easily

recognized icons, such as “?” and different animations freeze time to differentiate the

importance of different content to guide the player to find the hints.

Figure 1. Interactive Hints in Gorogoa

Humans like the challenge that do not exceed the limitation of their abilities, which in

puzzle game design means objectively solvable problems. Besides, humans always have

greater desires to work on something that they know will give them desired results. In order

to keep the beauty of the overall picture (Oosterbeek, Sloof & Kuilen, 2004), Gorogoa only

gives a simple hint of how to move the frame at the beginning of the game. However,

objectively, the lack of hints raise the difficulty of solving the puzzle.

In contrast, Shadowmatic, a mobile based puzzle game, in which players should rotate

abstract objects in a spotlight to find recognizable silhouettes in projected shadows, relevant

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to the surrounding environment, which provides players with more opportunities to acquire

hints. To start playing the game, players are requested to finish the tutorial level. The tutorial

level gives players two specific hints that will help players understand the game mechanics,

text guidance and image guidance. A progress bar directly below the screen will show the

completion of the current shadow. Due to the nature of free-to-play games, game designers

want to reduce the likelihood of players quitting the game, so they choose to consume more

game resources to give more hints to players.

Figure 2. Tutorial of Shadowmatic Figure 3. Formal Level

Figure 4. Shadowmatic interface, showing how resources can be used to acquire hints Figure 5. Level Loop

But Gorogoa and Shadowmatic have one thing in common. The player knows that the

information given by the game is hints. So the players have a very clear understanding that

they need to use this information to solve the puzzle. Another common way is to increase the

complexity of the game space, allowing the player to find hints themselves, for example The

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Room series.

Figure 6. Puzzle Solving Process of Room

Figure 7. Puzzle Solving Process of Room

In addition to the methods that are widely used to give hints in the puzzle game, such

as important props, visual tips and text prompts. There are trigger hints after clicking actions,

story hints appearing in the form of props and message comments, and puzzle tips that need

to be viewed in a specific box, and will be opened as the trial time increases. However, the

player needs to repeatedly view different spaces to obtain specific hints. This way of

obtaining hints and implementation lacks the ingenuity of the puzzle game, and is similar to

the "complete task" mode in the RPG game. But adding hints finding in the gameplay does

help the player to solve puzzles and have a better understanding of the game world itself.

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3. Game Design

3.1 Overview

Utolypse is a first-person perspective spatial puzzle game, which uses change in

perspective as its primary mechanic. During the game, player solves the puzzle by changing

the camera angle and the position of the character in the space environment. The puzzles in

the game are designed based on the specific game scene, and the player is given hints

through the specific association between puzzles to help the player find the solutions.

3.1.1 Tools

Compared to Unity 3D engine, we chose to use Unreal as our main develop

platform, because Unreal default materials and assets are of higher quality and it tends

to better suited for HQ/performance applications. Besides, the source code for Unreal

is public(Mueller, 2018). We also use MAYA, which can perfectly complete

modeling and texture work, as our 3D model editor.

3.1.2 Background Story

The story of Utolypose is inspired by scientific experiments conducted with

rats and mice in 1972 by John Calhoun. He built a mouse paradise with beautiful

buildings and limitless food, which called Universe 25. He introduced eight mice to

the population. Universe 25 started out with eight mice, four males, and four females.

By day 560, the mouse population reached 2,200, and then steadily declined back

down to unrecoverable extinction. At the peak population, most mice spent every

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living second in the company of hundreds of other mice. They gathered in the main

squares, waiting to be fed and occasionally attacking each other. Few females carried

pregnancies to term, and the ones that did seemed to simply forget about their babies.

They'd move half their litter away from danger and forget the rest. Sometimes they'd

drop and abandon a baby while they were carrying it. The result of Universe 25 gives

us a warning: If this behavior is shared by both mice and humans, can we escape

Universe 25's fate? (Esther, 2015)

In this game, the player becomes one of the last humans remaining. The reason

that humans are extinct is not because of a world war or nuke bombs. Instead, humans

build up a Utopia but everyone becomes selfish and only cares about themselves. The

refusal of responsibilities leads to some "beautiful men." (like the "beautiful rats" in

the experiment Universe 25, whose rats did nothing every day and only makes itself

beautiful without scars or bites. )

3.1.3 Goal

Like the mice in the Universe 25, players will wake up in a basement and find

themselves trapped here. So they need to take use of all the information they can

collect to find a way out of this space. Simply speaking, players need to find the

password for each locked door and then get out of this space.

3.2 Design

3.2.1 Puzzle Design

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In addition to the key puzzle in the tutorial, The key numbers are split into

several parts, each mapped to a different position in the scene. When the player

reaches a certain position, by changing the camera view, players can get the complete

number.

For the purposes of the study, the second and third puzzles were designed to be

associated puzzles. The second puzzle requires the player to find the number on the

door of the cell and enter it on the computer to open the door of the Basement. In this

puzzle, the player will be introduced to two mechanics of the game. The first is to

open a door by entering the password, and the second is the order of the password

numbers is related to the color sequence.

Figure 8. Hints of Color Sequence & Screenshot of one Puzzle

In order to get the result of the interactive design to enhance the player's

mastery of the method of solving the puzzle, two different versions of the A/B Test

will be designed on the second puzzle. One has the color sequence bar shows on the

screen will appear again, while the other will not. In the third puzzle, the player must

find the number in “Prison” and use the same color sequence to get the order. By

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comparing the two different versions, the length of time that players spent on solving

the third puzzle and records whether the player returns back to Basement to see the

previous color order to draw conclusions.

3.2.2 Spatial Design

- Basement

The tutorial level is based on a prison scene, which has a basement. According

to the background story, the basement is a secret experimental base which

stores a lot of human samples for experimentation.

Figure 9. Screenshot of the Basement

- Prison

Prison is the second main scene, after player solve the puzzle in the basement,

they will get into the prison building. There is only one puzzle in this scene,

which is finding the hidden password number. This puzzle requires the player

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to find the numbers in combination with the perspective and position learned

in Basement, and use the color sequence showed in the Basement to get the

right order and open the door to Prison.

Figure 10. Screenshot of the Prison

3.3 Game Design Research

Two playtest were planned in the game design research process, the first one is used

to test the gameplay and the puzzle's difficulty-increasing design. Based on the result, a

design iteration will be performed. The second playtest will be used to test the playability of

the game and the length of the game to facilitate the research test.

During the playtest, the total game duration of the participants and the time spent on

the individual puzzles will be recorded. After playtest, the participants will be interviewed to

get more data. The interview data will be re-interpreted to determine the gap between the

player experience and the game design theme, so as to make the next optimization plan.

3.3.1 First Gameplay Playtest

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The purpose of this playtest is making sure the game mechanics and aesthetics can

work as we expect.

- Result

1. Quantitative Data

First Playtest 29/01/2019: Prototype (Participants: 4)

Participants Time

Puzzle 1 Puzzle 2 Puzzle 3

1 30s 274s 163s

2 30s 55s 60s

3 28s 80s 30s

4 22s 60s 60s

From the result sheet we can easily find that, the average time of solving the

first puzzle is about 27s, so we can say that the difficulty of the first puzzle is

appropriate, the player can quickly grasp the unique way of solving puzzles in this

game. However, puzzle 2 and puzzle 3 show great deviations in the data. After

removing the maximum value, we will find that the average time to solve the second

puzzle and the third puzzle is 65s and 50s respectively. However, since the design of

the 1-3 puzzles is to teach players the mechanics of the game, the first player's

maximum value cannot be ignored.

1. Qualitative Data

Questionnaire: Only use for the design playtest

1. What do you think the game scene(game story) should be?

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Summary of Results

3 participants think this is a prison, the player has to try to escape from it, while a participant thinks this is a space capsule, the player plays the role of a spy and needs to escape from the place after stealing some important information.

2. Can you repeat what the three puzzles in the game are?

Summary of Results

Almost all participants can tell the specific content of each puzzle after the game. Three of the participants are aware of the hints in the third puzzle, and quickly solve the third puzzle according to the hints.

3. What do you think is the key to solve puzzles?

Summary of Results

All of the participants mentioned the need to pay attention to the discordant things in the game scene. These dissonant elements generally have certain implications and can help them solve the puzzles.

4. Have you played one of those game before? Shadowmatic, Gorogoa and Unfinished Swan?

Summary of Results The participants have not played the above games.

- Conclusion

Based on the qualitative data, it can be found that the methodology of the

game scenery design is different from the participants' understanding during playing

the game, but it does not affect the participants' game process. Although participants

do not have rich experiences in playing the puzzle game, they can quickly learn game

mechanics and discover hidden hints during the game. The difficulty of the puzzle in

the game is gradually increased, but it can be clearly found that the difficulty span of

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different puzzles is too large, so that the participants' game process is not very smooth

and used too much time in the second and third puzzles.

Therefore, in the iteration process, it is necessary to better coordinate the

game's aesthetic and mechanics, and at the same time reduce the gradient of difficulty

improvement between the puzzles, so that the player's game process is smoother.

3.3.2 Second Gameplay Playtest

The game which is used in the second playtest test is the iterative version based on the

results of the first playtest. The purpose of the second playtest is to test the mechanics of

puzzles and the hints we give in this version.

- Result

1. Quantitative Data

Seconde Playtest 21/02/2019: Prototype (Participants: 8)

Name Time

Puzzle 1 Puzzle 2

Participant 1 Video Broken

Participant 2 45s 105s

Participant 3 35s 113s

Participant 4 10s 111s

Participant 5 35s 165s

Participant 6 108s 72s

Participant 7 15s 192s

Participant 8 15s 98s

2. Qualitative Data

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Questionnaire: Only use for the design playtes 2.0

1. What do you think the game scene(game story) should be?

Summary of Results

Participants feel that they were in a prison, in which they need to find some hints to help them escape from that room.

2. What is your strategy to solve the second puzzle?

Summary of Results

1. 2 participants say they notice that there are disordered numbers on the wall so, at the time they are told to enter the password, they just go back to check these numbers. 2. 2 participants just entered random numbers such as 1111 or 1234, to see if it can work or not. They said that they didn't notice the numbers on the wall at first time, but after they saw the hints in the text dialog, they found the right numbers. 3. Other 4 participants said that after they are told to enter the password, they just looked around in the basement, and found these 4 numbers. They tried to enter the numerical order from left to right and right to left, respectively, and finally entered the correct password.

3. Do you remember the color order of the passwords?

Summary of Results

5 participants remember three of them and their order, and the other three participants can only remember less than or equal to 2 colors and their order.

- Conclusion

Based on the second playtest, it can be found that, after iteration, the unity of

the game aesthetics and the mechanics have been greatly improved. The difficulty

gradient of the puzzles in the game has been decreased, and the consistency of the

participants' game experience has improved. At the same time, in this playtest, the

game with hints version was tested. Participants generally believed that hints would

be of great help in solving puzzles. Not only that, but the information obtained in

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solving these puzzles have left a deep impression in the participants' minds, and can

help solve related problems in subsequent levels.

4. Game Research

4.1 Participants

There are 16 participants in this research, all of whom are older than 18 years old and

not color-blind. Participants agreed to screen recording during the playtest and accepted the

questionnaire after playtest, while allowing testers to use their data which is collected during

the playtest. These 16 participants will be randomly divided into two groups, one group will

playtest the version with hints and the other group will playtest the one without hints.

4.2 Procedures

The playtest will be carried out in a closed room with computers, tables and chairs.

Each participant will be given a number card before entering the room. After setting up the

screen recording service and other facilities, the participants will test the game in the room

alone. And after the playtest, the participant will be given a questionnaire survey and the

survey will be administered in person.

4.3 Measures

Here are the data collection instruments.

- Questionnaire Sheet

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- In-Game Data Collection Sheet

Game Data Collection

Group A: With Hints, Group B: Without Hints

Participant Group Participant Number Time: s

Puzzle 1 Puzzle 2 Puzzle 3

A

B

5. Result

5.1 Quantitative Data

The participants in group A played the game with hints and group B played the game

without hints. For some technical issues, the playtest data from one participant in each of the

two experimental groups are lost. Based on the usable data, we can find that, the complete

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rate of group A, which played the game with hints is 37.5% higher than the group B. For the

average time used to solve the puzzle 1 & 2, there is no significant difference between group

A and group B. But for the puzzle 3, participants in group B spent an average time of 60s

more than group A to solve the puzzle 3.

Game Data Collection

Group A: With Hints, Group B: Without Hints

Participant Group

Participant Number

Time: s Complete(Y/N)

Puzzle 1 Puzzle 2 Puzzle 3

A

1 17 60 112 N

2 15 25 187 Y

3 40 86 250 Y

4 38 10 230 Y

5 11 11 192 Y

6 5 59 104 Y

7 Data Lost Y

8 9 27 132 Y

Average 19.29 39.71 172.43 Complete

Rate 87.50%

B

1 36 33 157 Y

2 Data Lost N

3 31 38 232 N

4 71 26 222 Y

5 20 41 373 N

6 31 20 150 Y

7 15 27 355 N

8 10 16 134 Y

Average 30.57 28.71 231.86 Complete

Rate 50%

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5.1 Qualitative Data

It can be seen from the pie charts that the types of games that the two groups of

participants are good at are more evenly distributed, which can exclude the deviation of the

results of a group of participants who are more proficient in the puzzle game.

Figure 10: Left one from Group A, right one from Group B

By analyzing the results of questionnaire, we can find that the 87.5% of participants

in group A remembered the right color sequence but only 50% of participants in group B

remembered the right color sequence. Most of participants both in group A & B said that

following the context hints can easily solve the puzzle 1 & 2.

Strategy

Group A B

Strategy in Solving

Puzzle 1 & 2

1 2 1 2

1. Follow the context hints

2. Explore the basement, see the numbers and try the

1. Accidentally complete the key 2. Follow the context to the control room, try random

numbers, notice the color sequence bar then go back to check the numbers on the wall

1. Follow the context hints

2. Explore the basement,

see the numbers and

1. Accidentally complete the key 2. Follow the context to the control room, try random

numbers, notice the color sequence bar then go back

to check the numbers on the

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numbers in different

sequence

try the numbers in

different sequence

wall

Summary from

Solving Puzzle 1 &

2

Using the camera perspective to complete things, the password is not random and player needs to find them, may have a certain color

sequence?

Using the camera perspective to complete things, the password is not random, player

need to find the password numbers.

Strategy of Solving Puzzle 3

1 2 3 1 2 3

Find the exit first, and check the

color sequence on the numeric pad, then

looking for the number by using the camera.

Each number has a different structure, you can guess the number based on the pieces found and find the password according to

the color sequence

Find 3 obvious numbers, find the remaining

numbers based on the

color sequence, or

find the password by exhaustive

method.

Remember the color sequence

which used in the basement, and find that the numeric pad is same.

So just looking for the

numbers

Trying to find the numbers on the wall or inside each room but

failed

Looking for the exit and notice that there is a

small color bar, and then trying to find all the four numbers.

While asking about the strategy they formed after finishing the puzzle 1 & 2, 50% of

participants of group A mentioned that they found that there is a color sequence that maybe

an important hint, and only 25% participants of group B said that they noticed that the

numbers of puzzle 2 are shown in different color and thought that it maybe a hint. For puzzle

3, all the participants in group A noticed that there is a hint of color sequence, but just half of

the participants in group B notice that the password numbers should be entered based on the

color.

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6. Conclusion

In order to find out whether the interactive hints will help players solve the in-game

puzzles, we took use of two levels of Utolypse which has three puzzles. The first puzzle is

used to give participants an overview of this game and introduce some basic mechanics such

as how to use the camera to solve puzzles. The second puzzle gives participants two

significant information, enter a certain password to open the locked door and the numerical

order of the passwords needs to match the color sequence. These mechanics and hints will be

used in solving the third puzzle, which is located in the main prison building. Participants

need to stand at a specific location and adjust the camera to find the numbers and then, based

on the hint of color sequence to get the right order of these numbers. Finally, participants

enter these numbers, which will be the password of the entrance to solve this puzzle.

Through research, it is not difficult to find that hints can not only help players solve

puzzles during the game, but also help players to continuously improve the game strategy

during the game, so that players can better adapt to the rising difficulty of the game.

Compared to the context hint and image hint, the interactive hint will leave a deeper

impression on the player's mind. By constantly using interactive hints to enhance the player's

memory of a specific hint, it can not only reduce the need of space in the UI design for

storing hints, but also allow the player to focus more on the game itself.

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7. Discussion

For game designers, no matter which type of game is designed, it involves the

question of how to give the player hints. Traditional methods, such as context hints or image

hints, make it difficult for players to grasp the important information that the game has to

convey in a short period of time, thus unconsciously increasing the difficulty of the game.

The UI interface design provides the player with an information window that can be viewed

all the time. Although the game prompts can be effectively utilized, the content contained in

the UI interface is too complicated. Not only that, but players tend to look at them when they

need to, rather than remember, which affects the player's focus on the game itself.

Through research, we have demonstrated interactive hints, especially which is

interrelated are very helpful for players to master the game method and formulate their own

strategies. This conclusion can help game designers to find a better way to give players

important information.

Although for research itself, the limited number of participants in a single research

group may result in bias in the data obtained. Besides, there are only 3 puzzles in Utolypse,

and the average game time is about 6 minutes, which may have a chance to cause certain

research bias. During the research, group A and B respectively had a participant's playtest

data lost, and the influence of the data of these two players could not be ruled out.

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8. Appendix

[1] Video Records of Playtest: https://drive.google.com/drive/folders/1XdrwXRtXXJKfNVmbkCf4RAOO23QzYs_0?usp=sharing

[2] Surveys: https://drive.google.com/drive/folders/1qY6kAKrkHpwy_LOhkg507z6LkWXeUF8H?usp=sharing

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