Card Castle
Yes! That's where I live!
Me and, uh...
My... My dad.Lancer, Chapter 1
Card Castle (JP: カルタス城) is Card Kingdom's final area in Chapter 1 of Deltarune. It is located at the end of Forest, and is the home of King and Lancer. It has multiple floors, and contains two prisons that can be accessed via the far-right elevator on Floor 1F. It also houses the Eastern Fountain, which was created by the Knight. In the unused classroom, it is represented by a closet, although the closet has three racks rather than the six floors Card Castle has.
Enemies that patrol here approach to begin an encounter. However, they do not approach again once they are SPAREd.

Kris, Ralsei, and Susie arrive at the front of Card Castle after Lancer abruptly flees. As he closes the gate, the party gets ambushed and captured by an army of Rudinn Rangers.
Kris and Ralsei wake up in a shared cell in Prison B1. Ralsei asks Kris if they can find a way to escape. Susie informs them that she has the key, but is unable to solve the first card suit puzzle. Ralsei asks Susie to solve it, and she instead suggests they wait for Lancer. At Ralsei's suggestion, Kris assists Susie by telling her the buttons to press for the puzzle.
As Susie exits to free Kris and Ralsei, Ralsei inquires if Kris is worried about Susie. Either option causes Ralsei to suggest that Kris should imagine what Susie is doing. The scene then shifts to following Susie.

Susie explores on her own and hears Lancer's voice. In her concern, she solves the second card suit puzzle on her own. Upon finding Lancer, she explains that Kris and Ralsei are locked away. Lancer admits that he asked his troops to keep the party imprisoned. Susie reacts by refusing to listen and intimidating Lancer. She insists that he moves aside. When Lancer does not comply, she begins an encounter.
Susie repeatedly FIGHTs, with Lancer eventually not wanting to attack anymore. In the end, Susie admits she does not want to kill him, and Lancer explains his concerns for the party and his father. Susie reassures Lancer that they will not kill King, and reaffirms that they are still friends.
After the party reunites and uses the elevator, Susie asks Ralsei a few questions. Ralsei is surprised that Susie wants to ACT instead, and supports her. When Ralsei leaves the lift, Susie stops Kris before promising that she will listen to them, and is counting on them to make the right decisions.
As the party ascends the castle's floors, they are repeatedly impeded by Rouxls Kaard. Eventually, they confront King at the rooftop.
Most of Card Castle is entirely black, with white lines marking the floors and walls. Candles and posters often line the walls of the castle. It is divided into nine floors, including six main floors, two prisons, and a rooftop. The prisons and rooftop are marked with dark blue floors and walls, and are more detailed than the main six floors.
The Eastern Fountain, from which the Dark World is formed, is situated at the top of the castle. King and Lancer guard the Dark Fountain and aim to stop the Lightners from reaching it.

While locked in the prison cell, Kris can choose to consume the moss in the top right corner, which fully heals their HP. This choice transfers via Completion FILE, and Ralsei comments on Kris having moss. Returning to this cell and inspecting the moss causes Susie to be jealous. She also acknowledges that none was saved for her if Kris consumed it. Kris can also acquire the IronShackle at any time.
South of the prison cells in which the party is locked up, a pair of eyes is locked up to the left.
In Susie's cell is a Rudinn inside a trash can, whom she "invited" to get the keys. Kris can inspect the card suit puzzle here for Ralsei and Susie's commentary. Ralsei is pleased, while Susie is embarrassed.
To the right is a second card suit puzzle, which Susie solves on her own. Kris can inspect the completed puzzle to listen to Ralsei and Susie's commentary. She makes an excuse that it resembles a slot machine. In the next area is a forked path with a SAVE Point. North which leads to the elevator, and south leads to another jail area.

At the end are four Goulden Sams, which hold the three Former Kings who were imprisoned after the Knight arrived, a Puzzle Master who made an illegal word search puzzle, a Rudinn who did not want to fight, and a group of Cage Animals who have to live in one cage now that the Goulden Sams are occupied. Starwalker also appears if he was found and interacted with in the Forest beforehand. He mentions how the jail is "pissing [him] off", and declares that he is the original Starwalker.
After King is overthrown by Lancer, Lancer claims he is locked away in one of the prison cells.
Returning to Kris and Ralsei's cell and checking where the bars were prompts the text "(There's a conspicuous absence of a metal door here.)"

1F is associated with the Diamond suit. One of its corridors is guarded by Rudinn Rangers. Once spared, this Rudinn Ranger does not approach the party.
The castle gate is south on this floor. The elevator to Prison B1 and the ?????? floor is at the lower right. Inspecting the nearby sign reveals that Prison B1 was initially a basement.[1] North of this elevator is a second elevator that ascends to 5F. However, it is stuck at the top until the party rides it back down once.
The stairs to the next floor up are at the upper left.
The left side of the floor has a diamond-shaped door that leads to Rudinn's Room. The left Rudinn is proud to have sold beds in exchange for treasure. The right Rudinn praises the party for taming the "Talking Beast", and gives a free Choco Diamond. If Kris's inventory is full, Susie consumes it instead.[2] Alternatively, if the party defeated a Rudinn via FIGHTing, this Rudinn can be apologized to. The Rudinn accepts the apology, which can alter Chapter 1's ending if no other types of enemies were violently defeated.
This floor is not associated with a card suit, and is instead inhabited by four Dark Ponmen. If the SOUL gets hit by the attacks, it does 16 damage to each party member.
The stairwell down to 1F is to the left, and the north path leads to the next floor. It is initially blocked by spikes. The south corridor leads to a chest that contains a ClubsSandwich. To its right is a bathroom labeled "Royal Flush", which is a play on the hand in poker, as well as on the royal status of Lancer and King.

Going east leads to another room. It has a brief sparkle that appears on the far right of the room, which disappears when the party gets trapped by the spikes.
The party directly meets Rouxls Kaard for the first time. He gloats and expresses his confidence in his puzzle, which consists of a single block and switch. Kris can interact with Rouxls and listen to him taunt the party.
Solving the puzzle causes Rouxls to be speechless, then yell out loud before floating away. A Rudinn appears in this room afterwards, who appreciates Rouxls's puzzlemaking.

3F is associated with the Hearts suit. The stairwell down is located at its top center, from which each egress is guarded by Head Hathys. The corridors itself resembles a set of two hearts.
To the right, a room with a heart-shaped doorway holds four beds and two Hathys. If Kris inspects all four beds, their title changes from "Leader" to "Bed Inspector". The left Hathy is glad to have sold gems in exchange for beds. If the party violently defeated two or fewer Hathys, interacting with the Hathy on the right causes Ralsei to apologize, and Hathy forgives the party. This can alter Chapter 1's ending if no other types of enemies were violently defeated.
A stairwell up to 4F is located to the left.

4F is associated with the Clubs suit. The floor's upper area is guarded by four Scissor Dancers who move clockwise. If the SOUL gets hit, each party member takes 15 damage. On the north walls are also three Lancer portraits that Kris can interact with. Interacting with all three causes a splat sound to occur on the last one. This causes a chest containing ReviveMint to appear in the south side of the room. However, that path is initially blocked by spikes.
Rouxls Kaard appears again in the far-right room, which is similar to the previous puzzle room. He reveals his "ULTIMATE" puzzle, which is the same push block puzzle, but needs to be pushed twice. Kris can interact with him to hear Rouxls gloat. Once the puzzle is solved, Rouxls pauses and rescinds his statement. Ralsei inquires about Rouxls's other puzzle, to which he declines and slides away.
Returning to this room causes Rudinn to appear, who appreciates Rouxls. The Rudinn immediately apologizes for sighing so much, which was caused due to lack of sleep.

After solving the puzzle, the southern corridor opens up. At the lower left, the club-shaped door leads to Clover's room. At the lower right, the stairwell leads to Floor 5F.
Clover's room is decorated for her birthday party, including a set of three giant baseballs, and three trees. Interacting with Rudinn reveals it is the first party member, and is in charge of April 2012. Hathy explains that the commissioned cake for Clover was destroyed in a Field.

5F is associated with the Spades suit. To the left is Lancer's bedroom, which contains four holes and a spade-shaped bed. In the bed is Lancer's bicycle, which is tucked in. To the right is a shovel and a music player that plays a cartoon splat noise when interacted with. Along the northern wall are four identical portraits. Interacting with the leftmost hole in Lancer's room yields 20 "Rupys", which the narration states is not a useful currency.
To the right of Lancer's room is Rouxls Kaard's shop. Rouxls sells RouxlsRoux, Brave Ax, DaintyScarf, and Amber Card.
The far end of the floor has an elevator that descends to Floor 1F, which can subsequently be used to travel between 1F and 5F. Behind it is the staircase for Floor 6F.
On 6F,[3] Rouxls Kaard forces the party to fight K. Round. Rouxls explains that he has augmented it with a "Control Crown", which he admits is painful, but will not fall off as easily. If the party defeats K. Round and textboxes are quickly skipped via holding the [MENU] button, Kris can run to chase after the crown as it floats away. Inspecting it yields two different texts per inspection.
To the far right end is a staircase that leads to the throne room.
If the party returns to this area, C. Round can be found being peaceful.

In the throne room, a spade-shaped throne sits in the center of the room and is surrounded by treasure. The walls are decorated with tattered banners, similar to the exterior banners. Near the throne is Chapter 1's final SAVE Point. North of the throne room, the party continues ahead for the final confrontation with King.
If the party was peaceful, Kris and Susie can return to the roof area and back to the throne room.

The northern exit from the throne room leads to a short hallway to the rooftop. The rooftop is a long horizontal room with a square opening at the center. The opening features the Spade suit in the center and functions as the battle arena for the battle against King. The Dark Fountain can be seen in the background.
A stray pixel is present to the left of the Spade symbol.
The Dark Fountain is accessed east of Card Castle's rooftop, following a hallway that veers upwards and depicts the Delta Rune at its arch. In the room, Susie mentions that they are involved in something important. When Kris seals the Fountain, they and Susie end up in the school's unused classroom.

When the east elevator reaches ??????, the outline color of the elevator room changes from white to a faded dark blue.
This area consists of a long staircase that descends to Jevil's cell. It can be accessed from Floor 1F's east elevator. His door can only be opened with a Door Key, though it was split into Broken Keys A, B, and C.
When Kris inspects the door, they are presented with the option to use the key or not. Regardless of the chosen option, the Door Key will be used. The key causes a small door to appear within the larger door. Upon entering, Jevil begins an encounter.
Upon Jevil's defeat, the party is forced out of his cell, and the cell itself vanishes. When returning to this floor, The Circus no longer plays.
- The Card Castle's entrance
- ↑
(Formerly known as Elevator to Basement, Which Just Happened to Have A Lot Of Cages.)
— Narration for the east elevator sign on Floor 1F, Chapter 1 - ↑
Ralsei: I'm sorry, but we don't have any room...
— Ralsei and Susie, if inventory is full, Chapter 1
Susie: Too late, I already ate it. - ↑ The room is called
room_cc_6fin the game files.