|This paper describes the results of an experiment comparing two game modes in the game-based response system Quiz-a-tron. The goal of the experiment was to investigate how two different game modes affected the players' engagement, perceived learning, concentration, motivation, and social experience. In the game mode Reaction, your score depends on how quickly you give one correct answer. In the game mode Completeness, your score depends on how complete you answer is with a score multiplier for giving correct answers in a row. In the experiment, 30 students were randomly chosen. The subjects first played Quiz-a-tron in one game mode, then filled out a questionnaire, and then played the game in the other game mode and filled out the questionnaire comparing both game modes. Half of the subjects started with the Reaction game mode, while the other half started with the Completeness game mode. The results show that both game modes were perceived as fun, engaging, motivating, educational, stimulated to concentration, and provided a good social experience. Further, Completeness was perceived as more fun, motivating and a better social experience, and the students perceived that they learned more. The observations showed very different student behavior in the two game modes. The Reaction game mode was characterized by more students guessing answers, also for questions requiring mental calculations. In this game mode, most students gave their answer within the first 3 seconds when the time limit was 30 seconds. The "dead time" after giving answers was used to social bonding discussing questions and answers. The Completeness game mode made the students think more carefully about their answers and the pace of the game was slower. There was noticeably less frustration in this game mode. Also it was easier to fight you way back to the top of the scoreboard if the multiplayer was not lost. The observations also showed also the Completeness game mode produced less social interaction during the game.