The Roci escorts Giambattista through the open Ring, kills a pursuing attacker with its rail gun, and becomes the armed center of Medina's occupation.
The Rocinante escorts the damaged Giambattista toward the Ring and protects the assault's first wave while Bobbie Draper and Amos Burton disable the rail guns on Ring Station. Its compact size and Martian military armament make it the coalition's key surviving gunship beside the vulnerable carrier.
As Giambattista's damaged maneuvering thrusters delay the transit, the Roci tracks two returning Free Navy fast attackers. It clears the first Hail Mary torpedo attacks, enters the slow zone with the hauler, and allows one pursuer a chance to break off. When the ship instead follows through the Ring and launches six torpedoes, the Roci fires its rail gun through the enemy's drive, destroying the vessel in a magnetic-bottle failure.
The ship remains the operational heart of the aftermath: Holden broadcasts the surrender demand from it, its crew watches the slow zone settle into occupation, and its presence is part of the reason Bobbie believes Medina can only be held if more gunships arrive. The successful entry proves its power, but also emphasizes how thin the coalition's hard defenses remain.
A compact armed Martian-built gunship with active tactical displays, a keel-mounted rail gun, PDCs, hard-burn systems, and a worn but functioning combat interior after escorting a damaged massive hauler.
The Roci is the mobile military anchor that turns the disabled rail guns into a real occupation of the slow zone.
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