Carl drives the Nightmare Express through a switching station near station 436 and sees several possible routes, including Auxiliary Tracks, Station Repair, and Recycle. He also spots another train passing with human heads mounted on its caboose. When Donut reports that she has looted station 436 and that debris blocks the tracks near station 283, Carl decides to stop at Abyss Station 436 before returning, hoping to learn something useful while he still has control of the train.

At Abyss Station, Carl finds an empty platform with a single stairwell and climbs for nearly an hour while trains roar and crash all around him. At the top, he reaches the Abyss: a vast burning pit lined with countless portals and catwalks. Carl watches train cars burst from portals and fall into the pit, where jikininki janitors swarm over the wreckage. From this, Carl realizes the trains are not looping through time. Instead, the system discards the cars at the end of the line and sends only the engine cars back to a base to be reused.

Using his portal-analysis skill, Carl studies one of the portals and sees that the other side is a huge trainyard full of engine cars and zombie-like workers, with dwarves waiting outside the fenced area. He also notices a smaller portal and one of the rolling cages he has seen before. When monsters begin climbing toward his catwalk, Carl retreats with a smoke bomb rather than risk losing access to the stairwell. On the way down, he discovers that three items in his inventory can key the portal, including the seemingly worthless conductor hat, which means ordinary crawlers could reach the base if they know how.

Carl immediately sends a long message to his crawler contact network explaining what he has learned. He identifies confirmed and possible ways to reach the early-numbered stations and warns that each method carries serious risks, especially the zombie-filled trainyard and the dangerous employee portals. After answering replies, Carl returns to station 283, where Katia has cleared much of the debris from the tracks. He reunites with Katia and Donut, who proudly shows off a unique benefactor gift from Princess D'Nadia: fashionable goggles that protect her vision and turn her Magic Missile into a focused multi-target laser. Donut also reports that she has reached level 30 and gained a new special ability, Love Vampire, which redirects damage from her to an affected enemy.

In a safe room food court, Carl eats, opens loot boxes, and receives an enchanted toothpaste that greatly boosts his damage against bosses for limited uses. He assigns his stat points and considers taking the Nightmare Express through the portal, but messages from Elle and Imani complicate the situation. They report that Quan Ch appears to be destroying trains to farm engineers, stranding crawlers and forcing dangerous marches along the tracks. As Carl reads chat messages and remembers a passage from York in the cookbook about protecting one's unseen hive, Carl accepts that simply escaping may not be enough. By the end of the chapter, Carl does not yet know how to help, but he resolves that he has to try to do something for the crawlers being trapped across the rail system.