Moxana is one of the Muses built by master spark van Rijn for the Storm King. She plays games and tell fortunes, and seems to be exceptionally perceptive.
She traveled, along with her "sister," Tinka, with Master Payne's Circus of Adventure. Going through Sturmhalten, Tinka was taken by Tarvek and Moxana became more and more despondent. Agatha was going to try and build her a new sister, but Tinka and Moxana were once again united in Sturmhalten. Moxana has apparently decided to stay with Tarvek, as he is heir to the Storm King.