Design and Implementation of a Collectable Trading Card Board Game and Game AI Kristján Tryggvason Thesis of 30 ECTS credits Master of Science (M.Sc.) in Computer Science January 2016 ii Design and Implementation of a Collectable Trading Card Board Game and Game AI Thesis of 30 ECTS credits submitted to the School of Science and Engineering at Reykjavík University in partial fulfillment of the requirements for the degree of Master of Science (M.Sc.) in Computer Science January 2016 Thesis Committee: Dr. Yngvi Björnsson, supervisor Professor, Reykjavík University, Iceland Dr. David James Thue Assistant Professor, Reykjavík University, Iceland Dr. Hannes Högni Vilhjálmsson Associate Professor, Reykjavík University, Iceland iv Copyright Kristján Tryggvason January 2016 vi Design and Implementation of a Collectable Trading Card Board Game and Game AI Kristján Tryggvason January 2016 Abstract Both board games and collectible trading card games offer people an entertaining experience that requires formulating a strategy to win against an opponent. Trading card games, unlike board games, are traditionally played without using any kind of a board. However, by combining the two type of games we end up with a collectible card game with added strategic depth because of the complexities a two dimensional board adds. This allows the placement of cards and the card game gains new elements like distancing and movement, which adds more variety to game play. In this theses we design and implement such a game. The game is one of the first of its kind and poses various challenges to play intelligently, in particular for a computer AI. We do build such an AI for playing the game and evaluate it empirically. viii Design and Implementation of a Collectable Trading Card Board Game and Game AI Kristján Tryggvason Janúar 2016 Útdráttur Borðleikir og spil ýmiskonar eru meðal þeirra leikja sem fólk hefur gaman af að spila. Ein gerð af leikjum sem notið hefur töluverðrar vinsælda að undanförnu eru svokölluð safnkortaspil (e. collectible card games) þar sem leikmenn safna á hendi kortum með mismunandi eiginleika sem þeir svo spila út hver gegn öðrum. Ólíkt hefðbundnum borðleikjum, eins og t.d. skák, þá er yfirleitt ekki sérstakt leikjaborð sem spilað er á, heldur ráða einungis samsetning og eiginleikar kortanna þeirra leikjataktík sem nýst er við svo og hvernig leikir fara. Í þessari ritgerð munum við hanna og útfæra nýja gerð af leik sem sameinar eiginleika hefðbundinna borðspila og safnkortspila, þ.e. leikjataktíkin snýst bæði um að safna spilum með tiltekna eiginleikja svo og að spila þeim út á tvívítt leikjaborð þar sem hægt er að færa þau til á. Leikir sem hafa báða þessa eiginleika eru fágætir og krefjast aukinnar herkænsku til að spila vel, hvort heldur sem er af mennskum- eða tölvuspilurum. Auk þess að hanna og útfæra leikinn þá útbúum við tölvuspilara byggðan á gervigreind til að spila leikinn. x Design and Implementation of a Collectable Trading Card Board Game and Game AI Kristján Tryggvason Thesis of 30 ECTS credits submitted to the School of Science and Engineering at Reykjavík University in partial fulfillment of the requirements for the degree of Master of Science (M.Sc.) in Computer Science January 2016 Student: Kristján Tryggvason Thesis Committee: Yngvi Björnsson, Professor, Reykjavík University David James Thue, Assistant Professor, Reykjavík University Hannes Högni Vilhjálmsson, Associate Professor, Reykjavík University xii The undersigned hereby grants permission to the Reykjavík University Library to reproduce single copies of this Thesis entitled Study on Collectable Trading Card Board games and Associated AI and to lend or sell such copies for private, scholarly or scientific research purposes only. The author reserves all other publication and other rights in association with the copyright in the Thesis, and except as herein before provided, neither the Thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author’s prior written permission. date Kristján Tryggvason Master of Science xiv xiii Contents Contents xv List of Figures xvii List of Tables xix List of Abbreviations xxi 1 Introduction 1 2 Background 3 2.1 Strategy and collectable card game ........................................................................ 3 2.2 Existing games ........................................................................................................ 4 2.2.1 The Eye of Judgement ............................................................................. 4 2.2.2 Faeria ........................................................................................................ 6 2.2.3 Triple Triad .............................................................................................. 6 2.2.4 Others ....................................................................................................... 7 2.3 Background on Game AI ........................................................................................ 7 3 Design 9 3.1 General Description ................................................................................................. 9 3.2 Game Rules ........................................................................................................... 10 3.3 Content ................................................................................................................... 12 3.4 Example of play ..................................................................................................... 15 3.5 Summary ................................................................................................................ 16 4 Implementation 17 4.1 The Structure .......................................................................................................... 17 4.2 The Database .......................................................................................................... 22 4.3 Summary ........................................................................................................... 22 5 The AI 23 5.1 AI design ........................................................................................................... 23 5.2 State Evaluation ................................................................................................ 26 5.3 Empirical Evaluation ........................................................................................ 28 5.4 Summary ........................................................................................................... 29 6 Related work 31 7 Conclusions 33 Bibliography 34 xvi xvii List of Figures 1 Playmat for the game Eye of Judgment ........................................................................ 5 2 Showcase of on screen play from Eye of Judgment .................................................. 5 3 Picture from the game Faeria ..................................................................................... 6 4 Visual representation of board grid ............................................................................ 15 5 First half diagram of the system ................................................................................. 20 6 Second half diagram of the system ............................................................................ 21 7 Illustration of what a state contains ............................................................................ 24 8 Illustration of state search algorithm .......................................................................... 25 9 Illustration of Expectimax .......................................................................................... 26 xviii xix List of Tables 1 A table of unit cards ................................................................................................... 12 2 A table of structure cards ........................................................................................... 14 3 A table of item cards .................................................................................................. 14 4 A table of spell cards .................................................................................................. 14 5 Scoring formulas ....................................................................................................... 27 6 Results from playing full AI against a simplified heuristic AI with 200 games per match ......................................................................................... 27 xx xxi List of Abbreviations CCG Collectable card game RPG Role playing game TRPG Tactical role playing game GGP General Game Playing 1 Chapter 1 Introduction Games have played an important role in the development of artificial intelligence (AI), in part by serving as an objective benchmark of progress. One appealing aspect of using games for AI research is that they typically have a simple rule set for play, but require deep strategic insights for playing well. In particular, strategic board games like chess [14], checkers [15], and Othello [16] have received much attention, resulting in world-class level computer agents for playing those games. Subsequently other type of games, which incorporate additional strategic challenges, have become increasingly important test-bed for AI research. For example, Poker [17][18] adds both non- determinism and incomplete-information consideration, Real-Time Strategy (RTS) [19] games add a real-time decision making element, and General Game Playing (GGP) [20] an online