Diablo 1 HD Hellfire Mod | Awake

Have the developers of this mod ever released the tools that they have used to create this mod?

Or listed what tools they have used?

I used to make small Diablo 2 mods years ago for my own personal amusement. I was also having fun using the creation kit on Fallout 4 up until a few months ago.

I have started looking for tools to edit diablo 1 but have found most pages/downloads on the subject are few and far between with many dead links.

Nope. Beelzebub source code or any mod tools for it were never released and unfortunely never will be.

Only source code from Tchernobog 0.95dev(or even lower version) was sent to Freeablo main developer.

tl;dr - Beelzebub is not moddable.

btw. Beelzebub technically is not mod, but more like game written from scratch.

So it's developed with visual studio or a similar developer software? If so, how did they come up with the original part? Decompiling?

reverse-engineering i guess.