Randomness is one of the most important research areas in computer science and in particular, in cryptography. Security of almost all cryptosystems relies on random keys. Unfortunately, perfect sources of randomness are not easily accessible. However, True Random Number Generators (TRNGs) generate almost random strings, using non-perfect random sequences. A TRNG algorithm consists of an entropy source and an extractor. In this thesis, a TRNG is proposed in which a human player’s input in a two-player game is used as the entropy source and the random seed required by the extractor. This means that the proposed TRNG is only dependent on user’s inputs. The thesis contains the theoretical foundation of the approach, the design, and implementation of the corresponding game. To validate theories, we designed and implemented a game, and performed some user studies. The results of our experiments support the effectiveness of the proposed method in generating high-quality randomness.