Cassius, humiliated by his defeat to Titus, lets Darrow set his shoulder and, for the first time, calls him brother. Driven to rescue Quinn, Darrow and Cassius head east along visible ridgelines to bait House Minerva into attacking Mars. In a glen, they encounter a sharp Minervan girl on a mustang—Mustang—who deduces Mars’s shortages and that they’ve already fought Ceres.

When Darrow and Cassius try to unhorse Mustang, she signals her riders. Forced into a cold loch under stunpike guard, they wait through dusk as a distant smoke column—Roque’s signal—confirms Minerva rides for Mars’s keep. Near hypothermia and facing capture, they’re saved when Sevro emerges from the dark in a wolf pelt, ambushes the two sentries, and drives off medBots with his timing.

Sevro reveals he already stole and buried Mars’s standard and warns their plan lacks leverage: if Minerva topples Titus, Minerva will keep Mars’s lands. The new objective becomes stealing Minerva’s standard. Disguised on captured horses, Darrow and Cassius bluff into Minerva’s sprawling fortress using a password; a sentry’s question reveals Mustang’s given name, Virginia.

Inside, Cassius sets kitchen fires while Darrow destroys the warroom—shattering the atlas, carving “Mars” into the table, and sowing panic by shouting that Mars has overrun the towers. In the chaos, Darrow stuns the cook, June, and the pair steal horses and ride for the gate as the fortress erupts.

At the hidden back gate, Sevro intercepts a fleeing Minervan and captures the owl standard. Reunited, the three escape into the night with June and Minerva’s standard, laughing. They now possess the leverage to force Minerva out after Minerva helps bring down Titus.