This page contains spoilers about the Heartbound ARG. If you want to solve the puzzle yourself, avoid reading this article.
As of the time of writing this, little is known about Darksider Glyphs except their name (taken from game resource files). So far they have seen being used by the Barghest and Dark Lore. The Barghest speaks exclusively in Darksider Glyphs, while Dark Lore casts a spell in Darksider Glyphs on the Darksider Path.
If you enter the following code into the keypad in break room 103, you'll hear a faint laughter, and in-game Darksider Glyphs will be automatically translated from then on.
This code was discovered through Chapter 4 of the ARG.
Darksider Glyphs Translation Table
|English Letter||Glyph||English Letter||Glyph||English Letter||Glyph||English Letter||Glyph|