The original 1996 Diablo is playable now right on your computer’s web browser.
The browser port of the original Diablo was developed by Rivsoft, a team of developers who work on several Blizzard-related projects. However, the port would not be possible were it not for the work of a development team who in 2018 reconstructed the original source code for Diablo.
GalaXyHaXz and the Devilution team reverse-engineered the source code for the original Diablo last year in 2018. The project was meant to be archival, so the source code was reconstructed with all the bugs and bad code from the original 1996 version.
Source: IGN.com The Original Diablo is Now Playable on Your Web Browser