NetQi is a freely available model-checker designed to analyze network incidents such as intrusion. This tool is an implementation of the anticipation game framework, a variant of timed game tailored for network analysis. The main purpose of NetQi is to find, given a network initial state and a set of rules, the best strategy that fulfills player objectives by model-checking the anticipation game and comparing the outcome of each play that fulfills strategy constraints. For instance, it can be used to find the best patching strategy. NetQi has been successfully used to analyze service failure due to hardware, network intrusion, worms and multiple-site intrusion defense cooperation.