This position paper introduces a theoretical framework for the design of learning games based on the concept of experiential metaphor. Grounded in experiential learning and conceptual metaphor theory, the framework offers a method for integrating educational objectives directly into game mechanics. By considering the game as an adidactic and metaphorical environment, it proposes three principles of convergent design to help designers create coherent, meaningful learning experiences that avoid superficial gamification. A concrete example illustrates the model and opens perspectives for its empirical validation.