Game instructions play an important role in all games, as players always need them to help them understand the rules of the game. Constructivist learning theory and procedural rhetoric theory provide the theoretical basis for exploring unguided game instruction. This thesis aims to investigate two aspects of unguided game instruction, how it affects players' perceptions of the rules of the game, and how it affects players' perceptions of the message the game is trying to convey. An experiment was conducted with a control group and the results were analysed both quantitatively and qualitatively, based on objective data of the participants' performance during the game and their subjective answers in the post-game questionnaire. The main conclusion is that, unguided game instruction helps some players to construct an understanding of the rules, but it has no clear advantage in helping the player to understand the message the game is trying to convey.