Gallaron

Gallaron (also known as The Dark Magus) is a magus in the world of Dota 2. He is one of the possible creators of the spell alongside Tarak, having his name invoked with its incantation whenever this spell is cast.

He once arrived somewhere near the Howling Weald to build a labyrinth, but the settlement was unfamiliar with the magus, having never heard of him before. His obvious aptitude in the arcane arts soon convinced them that he was a magus. The locals spent resources building this labyrinth but ran into budget problems, something he cared little about. Nevertheless, the labyrinth appears to have been completed.

He owns a business called Quas Wex Exports.

Speculation
Due to sharing the same name as the final boss of the Dark Moon event, not to mention that said boss was accompanied by the so-called Agent of Gallaron, he may have been complicit with the advent of a Dark Moon.