First referenced in Marathon 2: Durandal, the W'rkncacnter, alternately described as both a singular entity and an entire group of creatures, is a mysterious and chaotic force that is rumored to trace its origins within the Marathon universe to the very beginning of time. It is documented within the legends of countless cultures, many long extinct, and it is present within the creation myth of the S'pht, wherein their ancient benefactors, Yrro and Pthia, settled on the S'pht homeworld of Lh'owon after first fleeing from the W'rkncacnter. According to the S'pht, it eventually arrived at Lh'owon, killing Pthia and angering Yrro, who retaliated by casting the W'rkncacnter into the sun, where it was burned but not truly destroyed. At one point in time, it is said that the W'rkncacnter was a discernible presence within the cosmos, but as the ages have progressed it has become much harder to detect against the backdrop of a myriad of similarly chaotic phenomena within the galaxy (i.e., stars, black holes, and their ilk).
The W'rkncacnter becomes an active component of the Marathon storyline during the events of Marathon Infinity, where it is revealed that the Pfhor's use of the trih xeem device, launched at Lh'owon's sun toward the end of Marathon 2, has had catastrophic consequences. Durandal relays to the security officer at the game's outset that the mythical W'rkncacnter did in fact reside within Lh'owon's sun, and that the trih xeem device has unleashed it. While normally calm and sardonic, Durandal is noticeably dismayed by this turn of events, fearing that they have been undone by the rash actions of the Pfhor. Driven by the desire to prevent the W'rkncacnter from enveloping everything in its unfathomable chaos, the player character in Marathon Infinity activates an abandoned Jjaro station that prevents the W'rkncacnter from expanding beyond the nova created by the trih xeem. Much of the game is spent reliving the events of the previous game under different circumstances, and though it is never explained how this possible, many have theorized that the W'rkncacnter itself is responsible for these sudden and disorienting shifts through time.
One of the defining characteristics of the W'rkncacnter as portrayed in the Marathon games is its seemingly incomprehensible nature. Durandal, for instance, a highly sophisticated A.I. construct, could not fully understand the creature when it first appeared, let alone combat it, saying that the W'rkncacnter obeys "rules that I don't comprehend." In one of the timelines of Marathon Infinity, the Pfhor's Admiral Tfear describes the aftermath of the W'rkncacnter's arrival, saying that it "cracked the shells" of his crew and "sucked the husks, tossing them unseen and shattering the spindle like a dried creche." He is not able to describe the beast itself, though he notices a "trackless whisper chattering through the hollow space" that "buzzes and threatens madness." These and other facts point to the likely conclusion that the W'rkncacnter may in fact be unknowable to a rational mind. This would also explain why the W'rkncacnter is described in some cases as an individual and in others as a group; being intrinsically chaotic, the W'rkncacnter may be both.