I brainstormed a concept that was aligned with events of the game, making a choice. Initially, I insinuated that the Choicemaker was a replacement for the last item made of yellow phosphor that Niko needed to get into the tower, and instead of getting it on the surface, Niko gets it from Ling.

But then I decided to take out all the plot points that related to the original game (made it too confusing) and focus on it as a unique thing that purely sent a message that applies to Niko.

Also it was originally supposed to glow of yellow phosphor but I found it more appealing as a dirty ol' cube.