Most studies on gamified learning have neglected gamification depth, which has motivated the current study to identify the impact of gamified depth on students' intrinsic motivation and performance levels. A quasi-experimental approach was employed, which involved a total of 117 undergraduate students divided into control (n = 57) and experimental (n = 60) groups. The students were exposed to two gamified platforms, namely Kahoot! for shallow gamification and Classcraft for deep gamification, over four weeks. The Intrinsic Motivation Inventory (IMI) served to measure changes that occurred in students' intrinsic motivation levels and the achievement test in the final lesson. Paired t-tests, an independent t-test and regression analysis were conducted to test the study hypothesis. Deep gamification significantly increased learners' intrinsic motivation level (+0.1845), while shallow gamification decreased it (-0.6439). Contrarily, students in the shallow gamified learning environment achieved a higher performance with a mean value of 73.42 compared to the counterparts in a deep gamified environment (50.83). Students' language mastery, interest, attitude and familiarity with technology were postulated to impact the study outcomes. Distinct subjects, age groups and a suitable experiment period are recommended for future studies to develop a proper gamified depth framework in the educational sector.