This is the cover for the soon to be released complete series box set of Sliders.
If you'll recall, Sliders was a 1990s TV series that told the story of a group of reluctant explorers who jumped from one parallel Earth to another, trying to get back home.Each week they'd travel through a dimensional vortex to an Earth that was different from ours in significant ways. They might encounter an Earth in which the Russians won the Cold War, or one inhabited by tribes of cannibals, or one in which women are socially dominant and men considered inferior.
It most definitely has nothing whatsoever to do with the Portal video game series. So why's the designer of the Sliders cover bending over backwards to make it look like it's Portal 3?
Didn't think I'd notice, did you, Sliders designers? Well I noticed. I noticed.