It was dormant for many years, and I have some old copies of the source code that may or may not work. There is no warranty, no promise that it works or compiles. But it's here.
Version 12.3e for MS-DOS, circa 2005, probably runs on Windows too
Version 12.5.1 for Linux, circa 2015
In 2016, a fellow named Gibbon started making some updates -- added color, improved the screen drawing, and such. A couple of bugs that I haven't been able to squash yet, but nothing major. Then he moved on to other projects, and I started making some minor updates and bugfixes.
I should point out that it was Gibbon and NOT me who added the Longsword of Hymie as a weapon. (I might rename it :) I adjusted the power slightly (I think "down").
Version 14.1.1 for Linux, 2019-03-25
Gibbon also started a plan to make major updates to Larn -- re-write into C++ (a language I don't speak), 80-column maps that change when you revisit a floor, increase the difficuly, add food and religion ... He didn't get very far before he gave up for other pursuits, and (to be frank) I'm not crazy about some of the changes he made (for example, you can no longer shift-move to run). But his last effort is here.
larn-gibbon.tgz for Linux, February 2018