Story Patterns are integral to Fujaba̢۪s approach to modeldriven development, providing the operational semantics the UML is missing. They can also be employed as a formal specification language. They have been used to specify transition systems and safety properties which are then formally verified. However, Story Patterns face some restrictions, notably with respect to negation. When used for a formal specification, they also lack features of logics such as quantification. In this paper, we propose Story Decision Diagrams (SDD), an extension of Story Patterns capable of expressing complex properties while retaining or surpassing the intuitiveness of the original visual notation. The proposed extensions include quantization, implication, alternatives, negation of complex properties, and a concept for modularity.