The research aims to investigate how the 2D slot game “Lucky Hero”, created for this research, could convey the story of Beowulf. The result of this study could provide experience and strategy for improving narrative design in casual games with similar mechanics. Also, this study is valuable to developers/designers who want to explore the potential of using casual games, especially slot games, as a storytelling tool. To answer the research question “How could the 2D slot game Lucky Hero convey the story of Beowulf”, a “research for design” qualitative study was conducted. The researchers examined theories related to narrative design, design in slot machine games, and folk mythology to develop the game. Playtests followed by interviews and adapted stimulation recall were used as data collection methods, and thematic analysis was used as the data analysis technique. The findings revealed that the existing design of "Lucky Hero" was not capable of effectively conveying the story of Beowulf to players. However, the study identified key elements that influenced players' understanding, such as graphics and game mechanics. The future narrative design of “Lucky Hero” should focus on improving immersion, character representation, and the connection between game mechanics and the story.