Diablo II version 1.12, downloaded from Google Drive: (this link says 1.13c but it’s a lie - we’ll get to that later) mac OS Mojave 10.14.x (I have no idea if it works on Catalina and I have no intention of finding out, ymmv) There are essentially 5 pieces you’ll need to make this work: Please take note of the versions because they matter.
Sorry if this seems too long, it’s by design, as I wanted it to be super clear so any idiot like me could get it running without needing to piece together varying advice and steps. It took me a hot minute to get this running and I ended up using several guides I found scattered across the internet, so I figured I’d try and converge them a bit so people don’t struggle in the future.