Portal 2 is a masterpiece (opens in new tab) and one of the few games that actually lived up to its hype (opens in new tab). Destroyed Aperture is a work in progress community-made Portal 2 mod that's been in development since 2015, and is due this year. It's as yet without a hard release date, but it's now popped up on ModDB (opens in new tab) with a bundle of new screens. I'm excited.
Because not only does Destroyed Aperture drop players into a neat/terrifying decayed and overgrown Aperture Science Facility, it promises a new five hour-long story campaign that spans five chapters. Within that, we can expect over 20 maps "filled with puzzles and exploration with increasing difficulty", and over 30 logic-based puzzles.
Here's the lowdown, as per its ModDB page (opens in new tab):
Destroyed Aperture is a free community made modification for Portal 2. You take the role of a man named David that gets woken up in an overgrown and decayed Aperture Science Facility 7. Facility 7's central core has failed and destroyed any and every communication systems along with the environment and killed almost everyone. The facility has been in a decayed state for years, locking everyone in. But not all hope is lost, there still is a chance of escaping.
Developer Dayin Creations cites (opens in new tab) "Fall 2018" as Destroyed Aperture's proposed launch window which, coupled with its appearance on ModDB, might suggest it's on track. Check out this FAQ (opens in new tab) for more on the minutiae, and have a gander at the following screens.