Current gaming literature lacks empirical evidence on the influence of game design elements and the process through which game engagement can transition into addictive behaviors. Drawing upon the dual theory of passion, this research explores how game design mechanics shape the dualistic experience of passion (i.e., harmonious versus obsessive passion) in mobile gaming consumption. Our netnographic study involved a 2-year participatory observation of an online mobile game community named Empires and Puzzles, culminating in 10,927 posts and nine relevant forum topics. Seven interviews with game developers were also conducted. Our findings reveal that specific mobile game mechanics, namely farming, loot boxing, and raiding, influence the transition from harmonious passion (HP) to obsessive passion (OP) through a pathway characterized by pre-occupying, whilst the recovery mechanism that facilitates the transition from OP back to HP include alleviating. Such findings foreground the theoretical importance of moving beyond a static perspective of gaming engagement. This study contributes to information system literature by developing an empirically grounded framework for understanding the mechanisms underlying the influence of game design on the dualistic nature of mobile gaming passion. Persistent public criticism and government skepticism can impede game businesses. Our insights have the potential to generate positive social impacts by promoting responsible game design to alleviate resistance and skepticism.