Modules are the main collectible of the game.
There are a total of 32 Modules across the World map, with 8 total available in each area. The player usually only needs 3 or 4 modules activated in order to progress to the boss area and the region's pillar. The purpose that the other 4 from each area serve is to open the 8-module doors in each area. These contain several Gearbits and other items.
The 4 pillars in the 4 main areas must be raised to gain access to the Abyss.
Modules are somewhat easy to detect due to the distinctive pulsing sound they make, which can help in locating them. The modules themselves appear to act as a sort of power source, as on several occasions machinery can be heard powering down and the lights dim when a module is removed.
Every time the fourth module is collected in an area, a nightmare sequence plays: The Drifter begins coughing up blood, and a nightmarish manifestation of Judgement appears, brutally murdering the Drifter. As the Drifter collapses, a series of disjointed images from the game's intro play before ending abruptly, as the Drifter wakes up without a scratch.