Active Debris Removal (ADR)—the task of extracting defunct satellites and fragments from orbit to ensure the long-term sustainability of space operations—raises a fundamental challenge of incentivization, as the effort produces global benefits but yields little direct return to individual actors. Prior work proposes a token-based reward for verified removals, yet its behavioral effects under competition, uncertainty, and limited coordination remain unexplored. We design and deploy a multiplayer serious game simulating an ADR economy with sequential investment, debris removal, and adaptive strategy. The gameplay reveals emergent behaviors such as strategic avoidance of high-value targets, informal coordination in the absence of communication protocols, and ethical tensions surrounding the removal of self-generated debris. Our findings suggest that serious games can function not only as institutional crash-tests but also as vehicles for public reasoning and critical reflection, offering insight into how novel governance mechanisms might succeed (or fail) when enacted by human agents.