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The Traveler Cage is an enormous countermeasure device designed to capture the Traveler and siphon its emissions of Light for Cabal use. This is a five-step process:
Despite cutting off its Light, the Traveler Cage does not necessarily restrain the Traveler itself, as it demonstrates the ability to quite easily break free with little apparent difficulty once roused. However, the process of harvesting Light from the Traveler may be physically traumatic: concept art depicts the Cage burning or blistering the Traveler's surface, and its reawakened form presents with even greater damage than before.
The Traveler Cage was at the center of the Red Legion fleet that attacked the City. Encountering no meaningful resistance from City defenses, the Traveler Cage docked with the Traveler unimpeded.
As The Guardian invaded Ghaul's flagship, The Immortal, the Traveler Cage carried out the second step of its deployment. The Guardian emerged onto the hull of the Immortal to see the Traveler wrapped in bands of black metal. When Ghaul confronted the Guardian on the deck of his ship, the Traveler Cage commenced step three, stripping the Guardian of their Light and leaving them helpless before Ghaul.
The Traveler Cage slowly carried out step four over the next week, as the Red Legion consolidated their control of the City.
By the time the re-empowered Guardian returned to liberate the City, step five had been completed. Though Ghaul was initially hesitant to seize the Light, he acquiesced in time to battle the Guardian atop the Immortal, Light against Light. The Immortal served as a conduit for the Light extracted by the Traveler Cage, infusing Ghaul with its power, though this also replenished the Guardian's own. Eventually, the Guardian slew Ghaul. However, Ghaul resurrected himself seconds later, transforming into a mountainous, ethereal figure of molten Light. Pleased by the vast degree of his new power, Ghaul turned towards the Traveler, asking if it would recognize him now. In response, the Traveler cracked open the Cage and unleashed a blinding burst of Light that annihilated Ghaul while also disintegrating the cage.
List of appearances