Analysis of the Impact of AI-based NPC with Different Levels of Initiative and Performance on Human Reactions

In the ever-expanding gaming market, there is constant demand to improve game quality. One of the key elements in enhancing quality is the Non-Player Character (NPC), which is a game character not controlled by the player, and is used for purposes such as balancing the game. Partic- ularly, the quality of NPCs influences the user experience in games in which human players cooperate with NPCs. Artificial intelligence (AI) is an effective tool for improving the quality of NPCs. In recent years, many developers have turned to AI to improve NPCs, aiming to make interactions less scripted and more adaptive. To investigate the effects of the characteristics of AI-based NPC as a partner, we developed an original game, where the human player connects to an AI-based NPC via a spring and they must work together to collect as many targets as possible. We prepared six types of AI-based NPC with different initiative and performance levels ; three levels of initiative (low, medium, and high) and two levels of performance (low and high). Eleven young people were participated in the experiment and we recorded the subjective rating of the gameplay experience and the performance of the human-NPC team. The results revealed that high-performance NPC had a positive impact on gameplay performance and satisfaction. On the other hand, it was observed that human players were unable to perform to their full potential when AI-based NPCs exercised initiative for long periods. The findings of this study are expected to provide valuable insights into the design of AI-based partner NPCs.