A new mod for Half-Life: Alyx was brought to light today courtesy of UploadVR. This mod, from developer wim.buytaert.1988, combines together Half-Life: Alyx with BioShock. The core idea here is that Alyx "crash-lands" in the underwater world of Rapture.
This is accomplished by using repurposed assets from Half-Life: Alyx in combination with new assets based on locations within BioShock itself. It's not a 1 to 1 recreation of BioShock, but it does reportedly offer some of the "core elements of much of (BioShock's) unforgettable opening."
The mod offers up around 25 minutes of gameplay at present. wim.buytaert.1988 says that they are unsure if there will be additional chapters.
Here is a short video showing off 15 minutes of this already short mod. I suggest that if you want to play it for yourself, you avoid watching the below video.
