This paper focuses on the benefits and utilisation of humour in digital game-based learning. Through the activity theory framework, we emphasise the role of humour as a mediating tool which helps resolve contradictions within the activity system from conjoining educational objectives within the computer game. We then discuss the role of humour within the digital game and its advantages for the learning process, in sustaining emotional and cognitive engagement, as well as stimulating social presence. We argue that humour makes the game experience more enjoyable, through emotional and persuasive arguments and characters that are more believable and interesting, thus in turn stimulating affective learning. We hope that through designing an engaging role-play, we can sustain personalised knowledge that encourages critical thinking.