The Crawler appears as a ghost-like being that tends to disappear and reappear as it pleases. Its body is small and thin in comparison to its oddly shaped head; regardless, it is still taller than a person even though it has a hunched posture. It has six large eyes, spikes protruding from the top of its pale head, a serrated looking mouth that stretches across the entire width of the head, long spindly legs. And very long, clawed fingers. It also appears to have a hump on the top of it's back.
The Crawler was the chief lieutenant of the antagonistic entity known only as the Corruption. In the waning days of the Old Kingdom, following the construction of the Tattered Spire, the Crawler attempted to enter Albion through a rift created by the Spire. In a desperate attempt to stop it, three heroes, Sol, Blaze, and Stone attempted to seal the rift to stop the Crawler. The closing of this rift resulted in a gargantuan explosion that shattered the Spire, destroyed the Old Kingdom, and turned the three heroes into Willstones. Unfortunately, the heroes were not powerful enough to kill the Crawler, and instead managed to seal it in Shadelight dungeon in Aurora. Many centuries later, Lucien's reconstruction and Theresa's subsequent reactivation of the Spire served to reawaken the Crawler five years prior to the events of Fable 3. A year later, King Logan visited Aurora and saw his entire escort wiped out by the Crawler. He was nearly killed himself but was nursed back to health by the native Aurorans in the City of Aurora. He promised to return and wipe out the Crawler, but never did. This was a turning point for him, and led to him becoming the tyrant he is shown as at the beginning of the game. It is later revealed that Theresa told him that the Crawler would attack Albion and that he must prepare.
Four years later, Logan's sibling, the Hero of Brightwall, also promises to help the Aurorans to gain support for their rebellion. This promise is either:
- fulfilled by formally making Aurora part of Albion and providing its people with protection, or
- broken, with the people of Aurora forced to work in a new mine just outside the city.
In either case, after deposing Logan and becoming the new King/Queen, the Hero has exactly one year to prepare for the inevitable attack by raising up to 6,500,000 gold coins to pay for an army to fight the Crawler's minions.
When the Crawler attacks, the Hero must fight their way through the Crawler's forces in Bowerstone Market. Toward the end of the battle, the Crawler possesses Walter Beck and becomes the final foe the Hero must face in the main quest-line. The Hero defeats the Crawler fatally but at the cost of Sir Walter's own life; a sacrifice Walter is glad to make. With his dying words, Walter thanks the Hero for driving away the darkness and tells them he is proud of them.
The power the Crawler exerts over the darkness is very complex and substantial. Similar to banshees, it is able to look into people's hearts and minds, see their greatest fears and use that information to demoralise them. For example, whilst they were in the desert, it continually mocked the Hero of Brightwall after they were forced to leave Walter, even taking the form of Walter and crying out "I'm blind!" referring to its previous actions having blinded him, before its voice twists from a mimicry of Walter's to a taunting, mocking tone.
The Crawler can cast hallucinations in people's minds, even to the point where even the landscape is transformed. In the final battle in Bowerstone Market the Crawler causes the following: sand dunes appear, bodies are thrown up against glass, crates explode as darkness breaks through them, pools of darkness that spawn children appear and the sun is blocked out.
The Crawler can also possess people, and can have a major influence over somebody who does not have the fortitude to resist it should this happen. It is possible that The Crawler is also capable of driving a person insane through its voice.