Eyes are often assumed to indicate deception. Yet, most studies typically used instructed deception directed toward screens or confederates. The present study introduced a novel paradigm from the Liar’s Dice game. Two players alternated between “bidder”, who rolled dice and made truthful or deceptive bids, and “challenger”, who judged the bid’s veracity. The challenger could contest, ending the round, or accept, becoming the new bidder who rolled new dice and made a higher bid. The challenger won if the contested bid was false and lost if it was true. Participants played against a computer in Experiment 1 (N = 36) and against another participant in Experiment 2 (N = 42). Three objectives were investigated: effects of non-instructed deception, deceptive social dynamics, and veracity judgments on response times, fixations and blinks. Across experiments, lying produced longer response latencies, fewer and longer fixations. Experiment 2 further showed fewer fixations on the opponent’s face when lying, and reduced blink rate. Challengers showed longer response latencies, fewer and longer fixations, fewer blinks when contesting a bid, but also increased attention on the bidder’s face. These findings suggest that non-instructed deception reduces eye movements and induces social avoidance, whereas suspicion also reduces eye movements but enhances attention toward the opponent.