Procedural content generation (PCG) can be a useful tool for aiding creativity and efficiency in the process of designing game levels. Mixed-initiative level genera- tion tools where a designer and an algorithm collaborate to iteratively generate game levels have been used for this purpose – taking advantage of the combination of com- putational efficiency and human intuition and creativity. However, it can be difficult for designers to work with tools that do not respond to the common language of games: game design patterns. It has been demonstrated that game design patterns can be integrated into PCG algorithms, but formally-defined and hierarchically-arranged game design patterns have not yet been used as a means of increasing gameplay-based control in mixed- initiative dungeon generators. We present a method for evolving dungeon rooms using multi-level game design patterns in the objective function of a genetic algorithm, as well as an instantiation of this method in a mixed-initiative dungeon design tool. Our results show that we are able to control the frequency and type of design patterns in generated rooms using pattern-related input parameters, enabling us to create dungeon rooms containing a wide variety of patterns on different levels of abstraction. Results from a small-scale user study of professional game developers suggest that the use of game design patterns in mixed-initiative level design tools can be a promising way of providing a good starting point when designing a level, as well as offering meaningful gameplay related feedback throughout the design process. We also identify challenges that will need to be faced if game design pattern-based mixed-initiative level design tools are to become a part of the game designer’s toolkit.