<p>This paper investigates the relationship between affective game design elements and player engagement in the context of indie games. Understanding this relationship is crucial given the increasing prominence of independent (indie) games and the emotional dimensions that shape the player experience. Success in the indie game market often hinges on gaining visibility within a saturated landscape, where many developers struggle to attract attention amid intense competition. Given the multifaceted nature of indie game development, it is essential to identify which design elements most significantly influence deep player engagement. Affective user-centred design (AUCD) is particularly vital, as it enhances player engagement by aligning emotional responses with gameplay experiences and design intent. This study adopts a quantitative approach, analysing survey data to establish statistically significant relationships between specific affective design elements and deep engagement. The findings provide valuable guidance for indie developers, helping them prioritise key design elements that evoke sustained player involvement. A rank-ordered AUCD framework is proposed, highlighting the game features most effective in fostering player engagement in the indie game development context.</p>