El Capitolio Nacional de Cuba is a recreated Havana landmark that serves as Carl and Princess Donut's point of entry into the Eighth Floor. A stairwell to the next floor lies behind a locked door inside its main hall. The pair first see the building as an empty, sealed starting chamber; when Carl returns near the end of the floor, it has become a contested exit. The fight for its keys kills Quan Ch and Chuluuna, damages the stairwell, and leaves Tserendolgor and Khulan behind as the building collapses.
Arrival in the rotunda
Donut chooses Cuba as the squad's starting region because she distrusts the apparent lead drawing Carl toward the Bahamas and Beatrice. She and Carl pass from the globe chamber into El Capitolio on the Eighth Floor's first day. Carl recognizes the building as Havana's historic capitol rather than the United States Capitol, which its interior initially brings to mind. Its hall has marble and tile, blue and magenta floor patterns, high arched windows, bronze-colored ceiling tiles, and a central cupola. Lamps give the otherwise dark chamber a yellow glow; a ribbon on one lamp marks the recreated setting as Christmastime.
At first they are alone. Their footsteps and conversation echo in the hall while Donut consults Mordecai about her new class. Carl tests the structure rather than assuming that its familiar appearance means it functions like an ordinary building. Several doors are locked. The door at the end of the hall has a level stairwell behind it, but the system tells him he needs a key. A tall window does not offer another route: the area outside is still locked, and he sees only dark, swirling smoke beyond the glass. He also cannot yet map the exterior. For the moment, the Capitolio is a contained arrival room with a visible but unusable exit.
Messages from other crawlers establish that this situation is shared across starting regions. Imani and Elle cannot leave their indoor arrival point in the western United States, and Katia reports a locked stairwell in Iceland. Carl tells the group he and Donut are in Havana. The Eighth Floor's announcement then explains that each region has two stairwells and that arrivals begin near one of them. Exit keys cannot be obtained during the initial phase. Only after the announcement do the outer doors open, allowing Carl and Donut to leave the Capitolio and explore the Cuba region. Thus the building supplies an early sight of the way down without letting the pair bypass the floor's card-squad and key contest.
A marked exit and an old trap site
The Capitolio becomes relevant again after the floor's initial phases. When the stairwell locations open, the system says a squad must use a key to unlock an exit vestibule; only members of that squad may pass through the unlocked door, and the key disappears when used. Carl and Donut's squad holds a key for El Capitolio, and the system marks the location on their map. There are five squads in the Cuba zone but only two of them hold keys. The building is therefore both their assigned way out and an obvious destination for crawlers who lack a key.
Carl has left alarm and teleport traps near the Capitolio's exit on the first day. Once the stairwells open, those traps activate, alerting him that another squad has approached the site. He realizes that the devices may scatter intruders but are too weak to settle a late-floor fight. He also catches himself imagining how much more destructive a heavily wired building would have been. The old traps nevertheless affect the immediate confrontation: Tserendolgor's team triggers them, and Khulan is separated from her companions while trying to return to the Capitolio.
The second Cuba exit is at a church guarded by Imani. Quan Ch appears there alone. Later, during a card battle against Carl and Donut and Sister Ines's team, he forces both opposing squads to play Flee cards. The resulting transfers give him the keys for both Cuba stairwells. Carl warns Imani and broadcasts a call to anyone guarding El Capitolio; Tserendolgor answers from the building. Quan can now seek either exit. Carl cannot simply arrange for him to hand over a key: fleeing a card battle risks losing a key the holder did not mean to surrender. Carl concludes that Quan is likely to choose the farther Capitolio door, where Tserendolgor's squad may not know his tactics. He warns her to watch for Quan's invisibility and to leave the remaining exterior teleport traps undisturbed. Chuluuna can see Quan even while the latter is hidden, giving the defenders time to prepare inside.
Carl and Donut are roughly fifteen kilometers from the Capitolio after their own battle moves them deeper into Havana. To reach the building quickly, Carl mounts teleport-trap anchors on small spider automatons and sends them with Samantha, whom he launches toward the site. He sets corresponding triggers where he and Donut are waiting. Donut stays behind to begin a separate card battle against duendes; this lets her summon totems that Carl plans to carry into the fight by teleport. Carl's scheme depends on the Capitolio being a reachable physical site outside the sealed stairwell chamber. Florin has already tested a stairwell chamber elsewhere and found that the system forbids placing traps inside it.
The fight before the stairwell
Carl teleports into the street near El Capitolio as Quan and Tserendolgor fight inside. Lightning blasts through the entrance, glass falls down the front steps, and smoke rises from other parts of Havana. Carl takes an invisibility potion before crossing the street. The building's main room, calm and empty on his arrival day, is now burning and crowded with combatants. Tserendolgor stands near the locked stairwell door with her flamethrower. Chuluuna, her ally and Khulan's husband, is beside her, as is her pet Garret, a large Tummy Acher. Khulan has not yet made it back from the teleport traps.
Quan hovers near the ceiling and uses cards to summon creatures. Tserendolgor has a mystic card that protects her hand from his interference, reflecting Carl's warning about Quan's methods. Carl sends spider automatons into the room as anchors for Donut's summoned totems. Donut herself remains at a distance, engaged in the duende battle. The separation allows her to supply fighters without personally entering Quan and Tserendolgor's card battle. Carl attacks Quan with a sticky explosive, driving him to the floor and weakening a shield while Samantha bites him.
Tserendolgor summons Basquiat, a giant Mongolian death worm, and gives it temporary protection. Quan's Toss-Up card immediately exchanges control of several active totems. The worm moves under Quan's command, devours his former summoned creatures, then turns against its original side. It tears through the floor and the entrance, worsening the Capitolio's structural damage. Chuluuna is killed during the reversal. Tserendolgor protects herself with a short-lived shell, but the worm continues to attack her and Garret. The door Carl and Donut once found quietly locked is now surrounded by combat that threatens to destroy the structure holding it.
Donut's reinforcements appear through Carl's spider anchors. Jola the Yule Cat rises toward the ceiling; Lazarus, combined with Skylar Spinach, also arrives. The worm swallows Lazarus, but Skylar's splitting effect causes stronger forms to emerge from the combination's destruction. Jola strips Quan of his clothing and protective cloak, dropping him to the damaged floor. Uzi Jesus and Asojano then batter him with attacks and debilitating effects. When Donut's distant battle ends, her totems vanish, but Quan is left blind, unable to heal, and badly hurt. Garret pushes Tserendolgor out of the worm's path just as her protective shell expires; she snares the creature long enough to survive its next lunge.
Before Quan dies, he asks Carl to return the simple gold ring Carl had taken with Quan's severed arm earlier in the crawl. Carl gives it to him. The ring's personal inscription and Quan's final remark briefly interrupt the fight's struggle over keys. His death ends the worm's attack. Donut receives the system's credit for the kill, so both of Quan's keys pass to her rather than to Tserendolgor, who is physically present beside the Capitolio exit. Khulan finally reaches the room and finds Chuluuna's body. The victory over Quan has removed a dangerous rival, but it has not put an exit key in the defenders' hands.
Damage, keys, and the last minutes
The system warns that the Capitolio's exit doorway has sustained damage and will become unusable in five minutes. If it crumbles, its associated key will disappear. Donut holds one key for the church and one for El Capitolio, but she is still elsewhere in Havana. Carl cannot simply pass the latter to Tserendolgor. He would have to bring Donut to the building and start a card battle so she could flee and drop a key; neither squad could choose which of her two keys the system would take. With minutes left, that gamble might strand Carl and Donut or leave Imani without the church key.
Carl considers using a teleport device to move Tserendolgor away and keeping the Capitolio exit for himself. That would protect him and Donut, but it would also consume the time and position needed to help Imani. Tserendolgor, meanwhile, refuses to make another squad fight for a key. She has just lost Chuluuna, and Khulan is grieving beside his body. She tells Carl that she will not continue by killing other crawlers for their way down. Carl argues that there are still days before the floor collapses and proposes finding another solution, but she has made her choice.
As the damaged wall sags, the system announces that the Capitolio stairwell is inaccessible and that all keys for it have been destroyed. The building can no longer serve as anyone's exit. Tserendolgor gives Carl her flamethrower, equipment, and cards. She also entrusts Garret to him: she uses a weapon that exploits one of the pet's weaknesses to kill him, allowing his regenerative cycle to return him as a level-one creature that can bond with a new owner. Khulan likewise gives up equipment. These transfers take place in the ruined hall where the squads had been trying to secure passage, and they leave Carl carrying resources and a pet rather than a usable Capitolio key.
Tserendolgor and Khulan remain inside. After Carl leaves with Samantha, Tserendolgor sets off an explosive bracer. Carl sees the Capitolio's dome collapse inward behind him, and Tserendolgor's name moves to his list of dead crawlers. He heads west through a burning Havana to reunite with Donut and continue toward Imani's church exit. El Capitolio's role on the floor has ended: the first stairwell Carl discovered has been destroyed, while the surviving key and the next escape attempt lie elsewhere in Cuba.