Few instructional design (ID) models exist which are specific for developing educational games. Moreover, those extant ID models have not been rigorously evaluated. No ID models were found which focus on educational games with complex learning objectives. "Ten Steps to Complex Learning" (TSCL) is based on the four component instructional design (4C/ID) model (van Merrienboer & Kirschner, 2007). However, the TSCL was not created specifically for educational games, nor were any studies found in which the TSCL has been used in this way. The primary focus of this study was to investigate the applicability of the TSCL for educational game design and how it might be improved for this purpose. Formative research methods were used to investigate the redesign of the Diffusion Simulation Game (DSG). When the original digital version of the DSG was played outside a formal classroom context with no instructional support, players were often overwhelmed by the complexity of applying diffusion strategies to persuade individuals to adopt an innovation. Thus, the DSG appeared to be a good candidate for redesign following the TSCL. Six rounds of formative research were conducted which included iterative design, development, evaluation and reflection. The TSCL provided fundamental guidance in initial stages of redesigning the DSG. Eight additional scenarios were developed and grouped into three task classes arranged in increasing complexity. However, the TSCL by itself was not sufficient. Guidance was found to be lacking on how to provide supportive and procedural information in a digital game environment, and on how to address strongly held player beliefs that contradicted their game experience. The unique, detailed design case in this study also contributes an important precedent for developing educational games. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]