Eco-gamification is increasingly recognized as a promising approach to address critical environmental challenges and support the achievement of Sustainable Development Goals (SDGs) of ‘net zero’ emissions and neutrality in land degradation by 2050. However, sustaining long-term engagement remains a challenge, which may be due to the insufficient integration of gamified media elements with visual representations of users' sustainability efforts. Building upon theory of media richness, this study proposes a ‘gamification-user-destination’ model to explore the psychological mechanisms underlying the connections formed between users and destinations through eco-gamification. Based on data from 308 experienced users, a higher-order model indicates that no single strategy can promote environmentally friendly behaviours. Instead, a moderated moderated-mediation effect is observed, suggesting that eco-gamification achieves optimal results when destinations demonstrate genuine environmental commitment. Conversely, superficial environmental campaigns can be counterproductive. This study contributes to the eco-gamification discourse by demonstrating how eco-gamification, in linking users and destinations, is geared toward sustainability goals.