Princess Chandra, a Naga lawyer whose uncle recently seized the throne, reveals her plan to exploit Carl and Donut for their wealth. Motivated by a desire to escape her home system, Chandra has used an old Naga law called Widow’s Rights to forcibly marry Carl, her late husband Rishi’s killer (Carl killed Rishi in Book 7 of the series). This action, combined with establishing a conservatorship over Donut, gives Chandra legal control of their massive shared fortune. She has also appointed herself Donut’s new attorney and hired assassins to eliminate the previous lawyer, Quasar.

Chandra presents the legal documents to Donut, expecting her to be defeated. However, Donut remains calm, compares Chandra to Carl’s abusive father, and calls her pathetic. When an enraged Chandra loses her composure, Donut warns her that she is not stealing from two crawlers, but from the entire Princess Posse. To any media watching the broadcast, Donut issues a thinly veiled but massive bounty for Chandra’s death. The threat is immediately effective; Chandra receives a message from her own assassins asking for her location. The interlude ends with Chandra terrified and completely intimidated by Donut, the power dynamic reversed.

Carl lands on the floor of the 10th level, still covered in gore from the end of the Faction Wars of the previous book. As Donut and other members of their team are dropped onto the floor, notifications tell Carl that only 5,501 crawlers remain in the game, implying 75 percent of them have taken deals to exit the dungeon. Carl is relieved for the exited crawlers, though he cannot think of leaving himself because of his urge to protect his friends and allies. Messages from former crawler Rosetta assure Carl she and Tipid are secure in the safe room. The end of the Faction Wars emptied the “Nothing”—a sort of vast backroom of the game—pulling unknown and uncontrollable gods into the dungeon. Consequently, all floors between the 12th and the 18th are in chaos (the 12th floor is the last known level of the dungeon; the upper floors are cloaked in mystery).

Carl also reflects that the god Scolopendra—the dungeon “boss” or the most powerful creature in the game—is now awake. Just then, the AI introduces two gremlins before Carl and Donut, each a mechanic who can set them up with a vehicle for the 10th-floor game. Donut chooses Hedy, the engineer powering the mechanical vehicle. Waldrip Chris, the other gremlin, deemed expedient by the game, explodes and dies.

As the challenge begins Hedy, frantically explains the rules of the 10th floor. The game is structured as a vehicle-bound race, with seven heats. The last-place team in each heat dies, and drivers in a team must rotate for each heat. A large wheel appears to randomly assign their vehicle. Before it lands, an unstable announcer broadcasts a message of despair, which is quickly cut off by another announcer, Zev. 

Zev officially names the 10th floor “Don’t come in last” and explains that 1,800 teams will compete in the heats. Vehicles are repaired between heats, and winners receive powerful upgrades. Zev’s briefing is cut short as the wheel selects their vehicle: a festive, seemingly non-functional Big Shot Chicken food truck with a large plastic gun obstructing the windshield. With the countdown nearing zero, Carl jumps into the driver’s seat and starts the engine, preparing for the first race with Donut.

A device called the Navitron 1000 announces the details for the first heat: a 53-kilometer course through the Caves of the Screeching Death Manatees. As Carl drives their truck, Donut uses her Torch spell to light the way, revealing strange opponent teams including a muscle car, a minivan, various creatures, and a unicorn’s head emerging from a giant tumbleweed. Reflecting on the chaos of the previous floor, Carl finds momentary relief in the more straightforward rules of this level.

However, a message from fellow crawler Prepotente warns everyone not to kill more than one opponent team per heat. He theorizes that if too many teams are eliminated, the system will fill the empty slots in future races with other crawler teams, pitting crawlers against each other. As Carl and Donut  near the cave entrance, they find a flaming, overturned minivan blocking the road. Simultaneously, a giant manatee kills another opponent—a bus-sized ladybug—and its rider explodes, meaning two racers may have already been eliminated and Prepotente’s dire prediction is likely to come true.

The crashed, burning minivan belongs to Team Free Love, a trio of bugbears, and its riders are not yet dead. The van is being attacked by a level 90 Screeching Death Manatee, a special guest creature. Donut easily kills the manatee and is given a choice: receive standard experience or let the audience vote on the creature’s fate. She chooses the audience vote. Carl helps the two surviving bugbears, Radoslav and Jasha, extinguish the fire on their van. They learn the third teammate, Alevtina, died in the crash. 

The bugbears reveal a stunning truth: They are self-aware NPCs who remember their past lives and deaths within the dungeon. They were offered a chance to race for their freedom, a new life outside the dungeon, and chose to participate. Believing they are now eliminated, they are despondent. To avoid a potential future heat against his own friends—which could happen if not enough teams finish—Carl decides to help them. He tells the bugbears he will tow their disabled van to the finish line, and they accept his aid.

While building a trailer to tow the bugbears’ damaged van, Carl and Donut are confronted by another team, Team Sparkles. The team consists of a belligerent unicorn named Dwight and a hostile, rodent-like mandagot named Lucienne, who ride an Avernus Creeper, an invasive species of weed. After Dwight and Lucienne insult Donut, their mount is startled by Mongo’s horn and tramples Carl’s trailer before racing ahead, leaving behind magical thorns that Carl collects for Mordecai, their guide in the game (Mordecai would be interested in the magically active biological artefacts).  Carl’s team tows the bugbears to the finish line. 

During the journey, they learn that a fan vote has mysteriously selected Otto the slime to be a manatee “stand-in” and that Elle, a human who used to be the resident of the Meadow Lark retirement home, is having an awkward meet-and-greet with her sole superfan. At the finish, the bugbear Radoslav thanks Carl for the temporary alliance, acknowledging they will be enemies tomorrow. The Royal Court of Princess Donut finishes in seventh place, while the bugbears, Team Free Love, finish eighth, just avoiding elimination.

Carl and Donut’s truck teleports to a garage where they meet Hedy. The increasingly glitchy AI announces the details for the second heat: a 10-kilometer race on one of two randomly assigned paths, each with a gatekeeper monster—a “boss”—that must be killed. The race will occur during a torrential downpour with giant hail, and a critical new rule states that Donut must be the driver of the truck. Hedy confirms they can hire up to three mercenaries (typically NPCs or dungeon-generated creatures) to drive, but she also recommends building a custom driving system for Donut. 

Hedy then presents their first vehicle upgrade choice, strongly advising a mobility upgrade over weapons or armor. The primary options are retractable spider legs, a hover upgrade, or special all-terrain tires. After considering how violent future races could become, Carl follows Hedy’s advice and selects the Retractable Legs upgrade. The chapter ends with Mongo and Rend—Carl’s and Donut’s pets, respectively a velociraptor and a giant meatball—making a mess after finding the truck’s frozen food supply.

Donut and Carl enter their safe room to receive gifts and upgrades after the last heat, and are surprised by Mordecai, their guide, in the form of a terrifying black-robed Moon Reaper with a flaming eyeball for a head. In a voice markedly different from his usual timber, Mordecai tells Carl that death awaits him at every turn. He turns to Donut to intone that she might be saved by a sacrifice in the end. As Donut nonchalantly asks Mordecai to go back to normal, he glitches between forms, settling in on the reaper, but in his normal voice. 

Mordecai tells them that he is unaware of what he just said to them. He is now a “shadow-mimic”—the worst of the changelings of the dungeon. Rosetta, a former crawler, says it is best to keep Mordecai sequestered from the others, given his current form of a shadow mimic. Meanwhile, Carla and Donut check their gifts. Donut receives a crawling, oozing spellbook called Oozy Form.

Donut reveals her other gifts, including a new unique hat, the Assassin’s Veil, which provides her a dexterity bonus and a precognition ability. Mordecai advises against draining its magic into her tiara yet as it would transfer a dangerous condition, leading enemies of the goddess Sekhmet to be hostile toward her. The group also examines two powerful new pet-only accessories: the Nemes of Pestilence and the Wrap of Sekhmet’s Compassion, both of which grant a pet temporary invulnerability when their owner’s health is critically low. 

Donut proceeds to open her 40 reward boxes, receiving many Emergency Gremlin scrolls for vehicle repair, and a special crossbow bolt called the Danforth. Her final celestial godslayer box, a reward for her War Crime spell, gives no physical item. Instead, the paw Donut used for the spell begins to glow painfully, and she discovers a new level of strength when she accidentally destroys the kitchen table with her claws.

Distressed by her lack of control over her magically enhanced claw and its blue color, Donut worries about accidentally destroying things or hurting Carl. Rosetta finds claw caps to sheath the claws and mute the glow, which Donut reluctantly accepts. Mordecai explains the boon also raised her Claw skill past its cap to level 17, making her a formidable melee fighter, but warns that the game will compensate for such power.

Donut also receives an Ice Slick spellbook and a new piece of armor, the Crupper of the Benevolent Champion. This crupper is part of a matched set with her cloak, and equipping it grants her significant stat bonuses. However, its item description contains a long, disturbing rant from the game’s AI about the brutal kill (the “War Crime” spell she cast at the end of the Faction Wars, instantly eliminating thousands) that earned her the “heroic” item, which visibly upsets her. Following the armor’s prompts, Donut chooses to raise her Puddle Jumper spell to level 16. The group then turns its attention to Carl’s rewards.

Carl reviews his recent achievements, which include “Bombs Away!” for dropping his inventory to escape Larracos, “Default Winner!” for his unsatisfying Faction Wars victory, and “Come to Daddy” for rejecting the exit deal. Opening his reward boxes, he restocks his bomb supply and acquires several notable items: Bomb Blanket potions, a Hotlist Expansion skill potion that doubles his quick-use slots, and a baby-carrier-style backpack that allows Donut to phase with him, which she promptly refuses to wear.

Finally, Carl opens the legendary fan box from the Naga viewers, expecting to find his marriage certificate to Princess Chandra. Instead, the box vomits out an enormous pile of burnt, wet, and destroyed junk, which is revealed to be all of Rishi’s personal belongings from his now-demolished home. The safe room is completely filled with the trash, leaving the party to deal with the overwhelming mess. Amid the wreckage, Donut is outraged to find unlicensed makeup palettes with her face on them.

Carl gives the white cleaner bot recovered from the Architect’s lab to Mordecai, who begins reprogramming it for their use. Later, the group goes to the garage and finds a crew of unfamiliar gremlins performing repairs on their vehicle. Hedy explains that these strange, silent gremlins appear after every race to do the main repairs before disappearing, and she suspects they are not real. As Donut makes Mongo and Rend wear the Egyptian-themed hats, Hedy advises Carl to learn which racers to trust. Carl states they trust no one, earning Hedy’s approval.

Carl and Donut enter the Team Roundabout, a safe, cul-de-sac-style hub area connecting the garages of the eight surviving teams. They encounter the bugbears Radoslav and Jasha, who are relaxing and drinking from a magical, self-refilling beer cooler. Their meeting is interrupted by the dramatic arrival of three Razor Fox ninjas (an NPC-team) from another garage. The leader, Chiyome,  joins Carl and Radoslav for a drink and proposes an alliance. She identifies the teams in the first three garages as major threats, specifically targeting the “womantaurs” of the Lady Dominators team in garage three as the group they must eliminate to stand a chance of winning. As she finishes speaking, the garage door for team three begins to open.

Two womantaurs—or female mantaurs - Genesis and Rapture, emerge from garage number three. Like the males of their kind, they have two torsos; however, in case of the womantaurs, the torso is placed lower, giving them the appearance of four legs. The womantaurs  are hostile and dismissive toward Carl’s group. Chiyome warns that the womantaurs practice domination magic. After they leave, the third member of their team is revealed: a half-mantaur (a male of their kind) split vertically and held together by a black vinyl suit. Chiyome explains this is the result of a spell called Split Personality and that the two halves can be re-fused.

Carl and Donut realize the half-mantaur is likely Corcunda or Corky, the long-lost friend of their NPC teammate, Dong Quixote. 

Carl decides it is best not to tell Dong about Corky to avoid the inevitable drama, but voicing this decision aloud triggers the AI to give them a new, two-part quest. The quest requires them to reunite Dong and Corky, find Corky’s other half (Porky), and then locate a fleshmancer to rejoin the two halves. The reward for completion is sending two stand-ins to the deadly Arena on the 11th floor.

Carl and Donut arrive in the Hungry Eyes Vendor Village, a neon-cyberpunk town where normal safe-zone and food-safety rules are suspended. Carl is preoccupied with the recent revelation about the 11th-floor arena, contemplating who he could force into the dungeon as a “stand-in” for mobs to cause the most disruption. While exploring, he locates the entrance to the Desperado Club inside a bar called The Hairpin and also spots a mysterious storefront advertising illegal modifications.

They head to their group’s meeting point, the Lollipop bar, and find the crawlers Jurgen and Prepotente arguing nearby. Against Prepotente’s advice, Jurgen is eating unidentifiable meat skewers from a vendor, hoping for a speed boost for their slow, tapir-like mount, Sweety. Despite insisting he has an iron stomach, Jurgen begins to vomit violently after eating the meat.

Carl and the others regroup with Imani, Elle, Florin, Louis, Chris, and their respective teams. The crawlers share updates on their assigned race vehicles, revealing a series of poor draws: Imani and Elle have a clumsy military vehicle, Florin and Lucia have a dangerous tuk-tuk, Chris’s team has a slow semi-truck, and Louis’s team has an impractical lowrider. Tran has a hearse, while Zhang and Li Na are using a biological octopus creature.

Florin reveals that Lucia’s personality has become unstable since the Faction Wars ended and she did not take an exit deal, prompting a concerned Jurgen to offer his help in intimidating her future race opponents. The group also discovers Elle is being constantly followed by a soother alien fan named Linus, who won an “extra access” tourist promotion by default as the only participant. Hearing about his friends’ terrible vehicle situations, Carl feels a growing sense of dread about how easily crawlers will be eliminated on this floor.

While the group relaxes at a bar, Prepotente asks Carl and Donut for advice regarding a dilemma. He reveals he possesses three unique “Enriched Pet Biscuits,” which have guaranteed, non-random effects. He shows them one called “The Paramour,” an item that transforms an animal into an upright, humanoid crawler and inflicts a permanent charm, causing it to fall hopelessly in love with the person who gave it the biscuit. 

Prepotente confesses he is lonely and wants to use it on Ragazzaccia, his goat girlfriend from before the dungeon. Donut is appalled, calling it a mind-control “sex slave” benefit and pointing out the extreme danger of turning Ragazzaccia into a level 1 crawler so deep in the dungeon. When Prepotente expresses his loneliness, Donut forbids him from ever using the biscuit and offers to mentor him on proper behavior. Prepotente agrees to her guidance.

Inside their race truck, Carl and Donut prepare with their designated driver, Bucket Boy. They discover the vehicle’s GPS is a sentient, sarcastic AI named Dr. Metcalf (after the therapist of Beatrice, Carl’s ex-girlfriend and Donut’s owner) that chastises anyone who touches its controls. 

While Donut finds a freezer that magically replenishes frozen food, Carl fails to remove a gun from the truck’s roof, blocked by a system notification preventing modifications. Dr. Metcalf displays the race details: They are on the left path of a 10-kilometer track with a required “gatekeeper monster” to kill, all during a torrential downpour with hail. Just as the race is about to start, Carl receives messages from his allies revealing a destructive development: Na has killed five other teams, and four replacements have been added, including Tran’s crawler team, forcing them to compete against an ally.

Carl’s team waits at the rainy starting line of the second race, positioned next to the bugbears’ van. The alliance has a plan to immediately eliminate the Lady Dominators: Once the race starts, Carl will shatter their windshield, allowing Donut to shoot the womantaur driver with a special rooting bolt. Chiyome’s bear mount will then smash the car, killing the immobilized driver. 

Just before the green light, the GPS announces massive hailstones as a new hazard, and one immediately destroys the awning covering the racers. The race begins, and Carl shatters the windshield. Before Donut can fire, however, Team Sparkles reveals a cannon and fires it at a team called Girth the Trouble, destroying their car and eliminating them. With their own plan preempted, Carl’s team is left sitting at the starting line as the other racers speed away.

Carl, Donut, and Bucket Boy drive their truck up a hill and pull alongside two other race teams stopped at the crest: the Lady Dominators in a burgundy GTO convertible and team One Fine Pig in a boxy armored vehicle. Carl maneuvers close to the GTO to benefit from its shield protection. Corcunda, the Lady Dominators’ crew member, is found unconscious in the back seat, which unsettles Carl.

At the center of Team One Fine Pig is a “throuple” involving two massive Tigran racers named Nico and Dario, and their beloved, Penelope, an ordinary Yorkshire sow. Penelope carries a magical curse that causes NPCs to fall in love with her, including the thunder god Taranis, who has placed a divine death-mark on anyone who harms her. One Fine Pig also includes a Taurin mercenary named Pontiff, who Bucket Boy recognizes as someone who once struck him. Carl instructs Bucket Boy to guard the One Fine Pig truck and, critically, not to hurt the pig.

Carl and Donut exit the truck and approach the gathered racers, at which point they see what everyone has been staring at: a boss waiting at the bottom of the hill in the middle of the road.

The race path is blocked by two identical, Level 170 kangaroo-like province bosses named Prison Pocket and Party Foul. The monsters are grieving the loss of their young in the storm and are attempting to capture racers to refill their caustic pouches, one of which contains a captive Upgrade Engineer. The racers on Carl’s road, including the womantaurs and the Taurin mercenary, agree to a temporary truce to defeat their boss. Nico becomes irrationally hostile toward Donut, whom he perceives as a threat to his pig mount. Across the valley, the other teams attack one of the bosses, but the creature proves difficult to defeat, fully healing itself by eating one of the razor fox racers they capture. Chiyome communicates that the monsters’ only weak spot is inside their pouches. Investigating a hunch, Carl has Donut examine the dead joeys in the pouch and learns they died of starvation, providing him with a clue for their plan.

Carl’s team forms a shaky alliance with the Lady Dominators to attack the boss, Prison Pocket the demon kangaroo. Their plan involves using a joey skin to enter the boss’s pouch. Carl and Donut summon gremlins as a distraction, which the kangaroo eats to heal. Carl then casts a spell and summons a creature called Little Günter, who rockets into the boss and knocks it over. In the confusion, Genesis of the Lady Dominators kills the human engineer NPC inside the pouch to take his joey skin.

Donning the disgusting, timed costume of the dead joey, Carl hops to Prison Pocket, who gets tricked and shoves Carl inside its pouch. Carl pulls himself to the bottom, plants two hobgoblin satchel bombs, and uses Gloom Wraith Phase to escape just as he detonates the bombs, killing the boss. The race ends with Carl’s team in seventh place. Carl levels up but discovers he is stuck in the foul joey costume for 12 hours.