While role-playing games and personalized learning have been regarded as effective tools to improve students' learning, incorporating personalized learning into role-playing games is challenging and approaches are limited to cognitive and motivational variables. Aiming at expanding approaches to incorporate personalization into role-playing games, this study included affective and cognitive variables to develop a personalized role-playing game, guiding by the situational design model. A pilot study was conducted to examine the effectiveness of the game on students' learning performance and cognitive load. Results showed that personalized role-playing game environment was effective in improving students' performance, reducing extraneous load, and promoting germane load. This study also found that although decreased extraneous load, could leave students more GL capacity for efficient learning, this would not necessarily lead to performance improvement. Students need to be motivated to invest sufficient germane load to actively process the learning materials and thus, improve performance. The findings have several implications for future research designing personalized educational games aimed to promote efficient learning.