My gamedev friend group got together and created an imaginary "franchise," a cast of characters and rough story outline. The concept was a cartoon series that never made it past the pilot phase called "Beep 'n' Zap," a Robot and Wizard duo who go on adventures trying to assemble a Giant Robot.
Given this premise, we all split off for a week and each made games that were part of the "Beep 'n' Zap extended universe."
This was the third jam I had done with this group. It's not a requirement to publish the games from these jams, so not all the Beep 'n' Zap games made it to itch, just as my previous 2 jam submissions didn't either.