Understanding the impact of interaction mechanics on the user’s emotional state can aid in shaping the user experience. For eliciting the emotional state of a user, designers and researchers typically employ subjective or expert assessment. Yet these methods are typically applied after the user has finished the interaction, causing a delay between stimulus and assessment. Physiological measures potentially offer more reliable indication of a user’s affective state in real-time. We present an experiment to increase our understanding of the relation of certain stimuli and valence of induced emotions in games. For this we designed a simple game to induce negative and positive emotions in the player. The results show a high correspondence between our classification of participants’ physiological signals and subjective assessment. However, creating a clear causality between game elements and emotions is a daunting task, and our designs offer room for improvement.