The Great Giana Sisters is a platform game developed by Time Warp Productions and released in 1987. It's known for its controversial similarities to Nintendo's Super Mario Bros, eventually leading to its removal from store shelves. Although there are plenty of similarities in terms of level design between the two games (with the first level being practically identical), the controls differ greatly compared to Super Mario Bros.
Publisher's Note: Both the Downloadables and YouTube Encode modifies the video of the Commodore 64's bootup to prevent any epileptic seizures. Please jump to 3:42 for the start of the run.