Krasko's vortex manipulator
From Tardis Wiki, the free Doctor Who reference
Krasko had a vortex manipulator which he used to travel in time. He acquired it after serving time in Stormcage.
Using the device, he travelled back to 1955, Alabama in an attempt to prevent Rosa Parks from causing the Montgomery Bus Boycott. There, he encountered the Thirteenth Doctor, who took the manipulator and stomped on it, destroying the device, but not after she had called it "cheap, nasty time travel." (TV: Rosa)
