We present a new tool called Cyclone that can be used for verifying and testing graph-based models. Different from other verification tools, Cyclone provides users with a unique way of building models and specifying their properties, by explicitly constructing and reasoning about graphs. As graphs can naturally capture both static and dynamic behaviours of a system, this allows users to represent many challenging problems. In this tool paper, we describe Cyclone’s basic features through different examples. Our preliminary evaluation results show that Cyclone has a promising potential in handling verification tasks from various domains and good usability for those who are not familiar with using verification tools.