bad guys

Conflict with Ink (Inkop!Sans): Ink tries to "fix" the multiverse and protect the AU, while Error tries to destroy it. This makes them natural antagonists. Confrontation with Nightmare (Nightmare!Sans): both feed on negativity, but their goals differ. They sometimes temporarily team up, but the alliance quickly falls apart.

Error!Sans's Past Origin and early years Error Sans is not a canon character in the Undertale universe, but an alternate version of Sans from an AU (alternate universe), where he became the embodiment of chaos and destruction. His story begins in an unstable, "broken" universe that was gradually disintegrating.

Initially, Error was a normal Sans in his AU—with the same personality traits: lazy, fond of jokes, caring towards his brother (Papyrus). But his world began to crumble due to external factors or internal imbalances. Disaster and Transformation The pivotal moment in Error's life was the complete annihilation of his home universe. The reasons vary depending on the fandom's interpretation, but typically include:

a massive failure of the multiverse;

influence of external forces (for example, Nightmare or other powerful entities);

The consequences of experiments with timelines and "Reset Mechanisms." At the moment of the world's destruction, Error somehow survived, but he was not the same:

Physical change: his body became composed of unstable energy and glitches - it constantly "glitches", flickers, distorts.

Psychological trauma: experiencing the destruction of her home and loved ones (including, likely, Papyrus) has caused a deep hatred for stability, order, and "perfect" universes.

Abilities gained: He gained powers related to the destruction of the reality code: the ability to "erase" other characters from existence;

manipulation of glitches and errors in the structure of the multiverse;

Immune to most standard attacks and effects (including Reset). Becoming a "multiverse bug." After the death of his AU, Error found no peace. He began:

Wander the multiverse, visiting different AUs.

Destroying stable universes is not for profit, but out of revenge and a desire to show others what it's like to lose everything.

Hunt characters, especially those who represent order or hope (such as Frisk).

Early Years: Guardian of the Tree of Feelings In the past, Nightmare, along with his brother Dream (Dream!Sans), was the guardian of the Tree of Feelings - a mystical tree that bore fruits with special properties:

The fruits of Dream were golden and gave people joy, happiness and positive emotions.

Nightmare's fruits were black and evoked negative emotions: fear, sadness, anger. Initially, Nightmare genuinely cared for his brother, the Tree, and his homeland. He served as a guardian alongside Dream.

The Path to Rejection Over time, the situation changed:

People came to the Tree in droves, but took only the golden fruits of Dream.

The fruits of the Nightmare were ignored—no one wanted to experience negative emotions. Attitudes toward the Nightmare worsened:

people began to avoid and shun him;

people whispered behind his back: “He is strange”, “His name means something bad”, “He guards the dark side of the Tree”;

Some began to openly mock him, throwing objects at him.

Nightmare hid the true cause of his injuries from Dream, claiming he simply tripped. Transformation into the embodiment of negativity Constant rejection and accumulation of negative emotions led to radical changes:

Absorbing negativity became the source of Nightmare's power, but at the same time it distorted his essence.

His physical form has changed:

the original appearance with white bones and pale purple pupils disappeared;

an unstable black mass appeared instead of a body; tentacles grew from the back;

the left eye began to glow blue - it constantly exudes negativity;

The second eye actually ceased to exist, symbolizing the destruction of the previous personality.

Nightmare lost most of his memories of his past. Only fragments of humiliation and eating black apples remained.

XTale In XTale, Cross (then known as Sans) was a royal guard who protected X-Frisk. He and his brother, Papyrus, joined the royal guard program after humans harmed Undyne. Cross was loyal to X-Gaster, X-Frisk's father, and did not immediately realize the extent of his manipulations. X-Frisk, in turn, tried to resist X-Gaster and his experiments. In one timeline, X-Frisk restored all the characters' memories of previous timelines in order to unite them against X-Gaster. However, Cross refused to participate in this plan and did not kill X-Gaster as X-Frisk demanded. This led to a confrontation: X-Frisk attacked Cross, scarring his face and nicknamed him "Cross." Afterwards, X-Gaster used his "Reset" ability, reverting events to a previous point, and Cross forgot about the incident. Later, when X-Gaster created X-Event (an experiment using Chara's soul and X-Frisk's body), X-Frisk attempted to force Cross to kill him to prevent X-Gaster from overwriting the universe. However, the plan failed: Cross destroyed X-Frisk's body and absorbed X-Event's soul, becoming the new X-Event. However, he was unable to use the Overwrite ability, as his monster body was incompatible with the ability, designed for a human vessel.

Error!Sans (Error!Sans)

Deputy leader, destructive analogue of Ink!Sans.

Responsible for "cleaning" the Multiverse - erasing glitched AUs.

It seems cruel and heartless, but in reality it maintains a balance between creation and destruction: the Multiverse does not have time to adapt to too many AUs.

Considered the smartest in the team.

Dust!Sans

Cold and apathetic, very reserved and silent.

He rarely talks to others, but often talks to himself—in fact, he is communicating with a hallucination in the form of Papyrus.

One of the laziest in the group.

Second favorite member of Nightmare.

Has a strange love for dust.

5. Horror!Sans (Horror!Sans)

Often considered the hungriest of all, he empties refrigerators, which are immediately replenished.

It may seem like a crazy destroyer, but the reason is long periods of famine in the past.

At times energetic and talkative, although speech can be slurred.

Generous, he is the easiest to influence

Relationship history:

The Beginning of a Friendship. Initially, Cross and X-Chara were close friends. X-Chara, ambitious and charismatic, saw potential in Cross and offered him an alliance. Cross, hungry for recognition and friendship, seized the opportunity. Hatred and a thirst for revenge. After the betrayal, Cross developed a burning hatred for X-Chara. He swore revenge and began to purposefully seek ways to destroy his former friend. Complex emotions. Despite the hatred, Cross cannot completely erase X-Chara from his life. Deep down, he still remembers the time when they were friends, and it evokes mixed feelings: pain, anger, and the bitterness of loss.

A Cycle of Violence. Their relationship often devolves into a cycle of clashes and conflicts. They sometimes try to destroy each other, sometimes are forced to temporarily unite against a common threat, which only complicates the situation. Mutual influence. X-Chara sees Cross as a dangerous but intriguing adversary. Sometimes he provokes Cross into action simply to see how he will react. Cross, in turn, serves as a kind of "mirror" for X-Chara—a reminder of the consequences of his manipulations. Bottom line: Cross and X-Chara share a deep and painful history. Their relationship is a mixture of friendship, betrayal, hatred, and lingering affection. This bond shapes much of Cross's motivations and actions, making him one of the most tragic characters in the fan universe.

Cross's character (Cross!Sans) Cross is a complex and contradictory character with a difficult history. His personality was shaped by trauma, betrayal, and loneliness.

Key character traits:

Aggressive and quick-tempered. Cross often reacts to stress and provocation with violence. He is not prone to lengthy negotiations and prefers to resolve problems by force. Suspicious and distrustful. Due to the betrayal he experienced, Cross trusts no one completely. He expects a trick even from those who try to help him.

Loneliness and inner emptiness. Despite his outward rudeness, Cross is deeply lonely. He longs for true friends, but fears being betrayed again.

Vulnerability beneath a mask of cruelty. In rare moments of candor, Cross reveals that he's still capable of empathy and caring—but he carefully conceals it. Purposefulness. When Cross sets a goal, he pursues it head-on, disregarding obstacles and the interests of others.

Impulsiveness. He often acts without considering the consequences, which leads to new problems.

Sense of Justice (Distorted). Cross has his own idea of ​​"justice," which can differ greatly from the generally accepted one. He is willing to punish those he considers guilty without trial or investigation. Character Origin. Cross's personality is believed to have been shaped by the tragic events of his AU: he lost loved ones, faced betrayal (it is often mentioned that he was betrayed by someone he considered a friend—X-Tale!Chara / X-Chara), and was left alone with his traumas.

Cross!Sans

Antihero: Doesn't like to cause pain, but only does so when necessary.

He joined Nightmare out of gratitude - he took him in when Ink couldn't.

Cold and intimidating on the outside, but inside he is a compassionate man who has been treated unfairly in the past.

He cares deeply for his comrades and often consoles them.

Epic!Sans' best friend, he likes Dream!Sans not because of his positivity, but because of his personal relationship with him.

The Star Sanses The Star Sanses are a group of three skeletal Sanses in the Undertale universe, self-proclaimed guardians of the Multiverse. They oppose the Bad Guys and strive to protect alternate universes (AUs) from chaos and destruction. Team members Ink!Sans:

Role: Drawing Master, AU Protector.

Personality: Energetic, sweet, but sometimes chaotic. Easily forgets things, so he writes them down on his scarf. Without paint, he becomes insensitive.

Capabilities:

High-level regeneration (can recover even after destruction); bone manipulation (stronger than classic Sans);

teleportation between timelines and AUs through paint liquid;

ink creation and manipulation (can create structures like the Scribble Sphere with 350+ AU);

Immune to manipulation of souls and emotions (due to the absence of a soul). Dream!Sans:

Role: keeper of positive emotions, team leader.

Personality: kind, caring, talkative, sometimes dramatic. Brother of Nightmare!Sans.

Capabilities:

absorbing happy emotions for healing and empowerment;

Traveling between AUs using positive energy;

Weapon: Golden Staff with Stars (can transform into a bow); Underswap!Sans:

Role: Team Member, has similar traits to Underswap-Papyrus.

Personality: Confident, immature, loves mysteries, and has a big heart. Collects sci-fi figurines.

Capabilities:

soul manipulation (colors the souls of opponents blue);

bone manipulation;

using Gaster Blasters;

Features of interaction Dream!Sans serves as the group's leader and coordinator, using positive emotions to unite the team.

Ink!Sans creates and restores AUs, drawing new worlds and characters.

Underswap!Sans provides tactical and combat support, using his abilities in battle.

The team's plan is to combine forces to destroy and subjugate various universes. They act as antagonists to the Star Sans, a group that, by contrast, seeks to protect the Multiverse. The team's leader is Nightmare!Sans. He is a cunning, strategic, and manipulative character who seeks to replace the family void left by his breakup with Dream with connections to his teammates.

Bad Guys typically include:

Killer!Sans - known for his violent tendencies and use of a knife. Dust!Sans - was convinced to join the team after initially rejecting the offer. Horror!Sans joined the group in exchange for food, as he was in dire need. Error!Sans was the last to join the team. Although he initially refused Nightmare's offers, he later saw the benefits of an alliance with him and agreed.

Cross Sans (XTale!Sans) is a character from the Underverse and XTale universes, an antihero who regrets his actions. He is a short (about 140 centimeters) skeletal monster with white irises. Appearance Basic image:

wears a black T-shirt, a white unbuttoned jacket with short sleeves and a hood; the letter X is depicted on the shorts and belt; wears a long scarf secured with two crossed belts and a gold heart-shaped medallion. Additional details:

There is a red scar on the right cheek - a trace of Frisk's attack; The right eye is red (due to Cross previously having control of the ball from X!Chara); the left eye is blue-yellow (due to blue magic); In some versions of the image, the jacket is tied to the belt, and the torn sleeves are tied around the forearms and the hilts of the swords. Past Cross lived in the XTale universe created by X!Gaster. As a child, he met Frisk when the latter fell into a dungeon. Before becoming a royal guard, Cross wore a white jacket with a fur-lined hood (black on the inside) and a hat with a pom-pom.

When X!Gaster tried to teach Cross, Undyne, and Papyrus to fight to protect Frisk, they initially refused to learn, wanting only to play. But after humans caused great damage to Undyne, Cross and his brother began training to protect Frisk. Later, Chara and Frisk hatched a plan to use Cross to overthrow X!Gaster. Frisk overwrote Cross several times, but X!Gaster used RESET, reverting events to the last OVERWRITE.

At some point, Frisk decided to show Cross what their life could be like without X!Gaster, but Cross refused to change anything. Frisk then attacked him, leaving a scar on his face and nicknamed him "Cross" (from the English word "cross") because of the design of his clothes. After this, a RESET occurred, and Cross forgot everything. After the destruction of the XTale universe, Cross remained with X!Chara, whom he had trapped in his body. He later met Ink and eventually became friends with him.

Error (Error!Sans) is a skeletal monster, an alternate version of Sans from Undertale, created by LoverOfPiggies. His appearance differs from the canon character in several ways. Physical characteristics View. Skeleton with black, red and yellow bones. Height: About 165 centimeters (5 feet 4 inches). Weight: Approximately 30 kilograms (67 pounds). Gender: Male. Appearance: Eyes. The right pupil is completely white, the left is blue with a yellow ring around it and a black pupil in the center. The whites of the eyes are red. The right eye is smaller than the left. Blue streaks extend from the eyes—the result of accidental magic use on the sockets. Face. The inside of the eye sockets and nose are red. There are blue streaks on his face, reminiscent of tears. When extremely angry, his eye sockets can become covered with numerous "Error" signs, rendering him temporarily blind. He wears a black coat with yellow pockets. Pieces of blue fabric are sewn onto the sleeves. Under the coat, he wears a red sweater. He wears wide black pants with pieces of blue fabric sewn unevenly at the bottom. He also wears a long blue scarf and black sandals. Additional features Error's bones are covered in the word "Error". Gaster blasters (weapons) are black with "Error" lettering and blue "tears" falling from their red eye sockets. They are faster and more powerful than those of classic Sans. When embarrassed, Error blushes blue. Suffers from haptophobia - fear of touching. Basic abilities Thread manipulation is a key ability. Error extracts threads from the stripes under her eyes; each type of thread has its own purpose:

Blue Strings: Extract code and data from alternate universes (AUs), absorb energy, and limit the opponent's mana, defense, and health. Error Blasters are similar to Gaster Blasters, but are more powerful, faster, and larger than the classic Sans's. They are black, with the word "Error" written on them and blue "tears" falling from their red eye sockets. They fire red beams with a range of 3 meters; they can absorb reality around them. Teleportation.

Dust!Sans' appearance Dust Sans is a skeleton that looks similar to the classic Sans from Undertale, but with a few dark differences:

Clothing. He wears a blue hoodie with a white hood. His clothes are covered in dust—the remains of the monsters he's killed.

Eyes. The left eye has an unusual coloring: the iris is dark red, and the pupil is blue. Because of this, a purple smoke trail (a mixture of red and blue) emanates from the eyes.

Height: 5 feet (approximately 152 cm). Special details: A ghostly image of his brother Papyrus often appears next to him—only his head and arms, no body. The ghost has red eyes, red gloves, and a scarf. This image is visible only to Dust Sans himself. Dust Sans's past Dust Sans' story takes place in an alternate universe (AU) where he tries to stop a man who is committing genocide against monsters:

An attempt to stop genocide. Dust Sans decides to stop a man who repeatedly kills all the inhabitants of the Dungeon and resets the timeline. To become strong enough, he is forced to increase his level (LV) by killing monsters. The futility of sacrifice. Caught in a cycle of resets, Sans realizes that killing doesn't give him enough experience to defeat the man. After resets, his level doesn't drop to one, but he gradually loses his original purpose.

Loss of sanity. Over time, Sans stops feeling guilty about killing. He continues to kill to become stronger, and eventually reaches the hardest step: killing his brother Papyrus, believing it's better than Papyrus's madness and hallucinations. After Papyrus's death, Sans completely loses his mind. He begins to be haunted by his brother's ghost (known as Phantom Papyrus)—either as punishment or as his own mental coping mechanism.

Becoming a killer Initially, Killer Sans was like the classic Sans—laidback and lazy, with a penchant for jokes. The turning point came when he encountered Chara, a character with genocidal tendencies.

Chara offered a deal: Sans would help her commit genocide (the mass extermination of the Underground's monsters), and in exchange, she would spare his life. Sans agreed, at first likely out of fear and a desire to survive (he had only 1 HP). In subsequent timelines, Sans and Chara repeatedly committed genocides. The repeated cycles of murder and world resets (via the RESET function) gradually warped his psyche.

A key moment in Killer's past is Chara's betrayal. In one timeline, in the midst of yet another genocide, Sans killed Chara, absorbed her Hate Soul, and left Killertale. From that moment on, he began committing genocides independently, without any external pressure.

Horror!Sans is a character from the Horrortale universe, an alternate version of Undertale. His appearance differs significantly from the classic Sans due to his traumatic experiences and years of starvation. Clothing Horror Sans wears a blue hoodie, covered in dust and blood—both his own and that of his victims. Instead of his usual slippers, he wears blue tennis shoes. Black shorts with white stripes on the sides remain part of the outfit, as does the white shirt, but it's stained with blood. Some versions of the outfit are completed with a furry, tattered hoodie instead of the usual jacket. Physical Traits Broken Skull. Sans has a large hole on the left side of his head, left by Undyne's spear. This injury has caused changes in his appearance and psyche. Eyes. The right eye glows blood-red. In some versions, Sans has a red eye, which he took from a dead guard after Undyne deprived him of his "magical" eye. The left eye may be completely black with a red pupil. Magic Crisis and Famine. The Underground's main magical source dried up, leading to a famine that caused monsters to turn to dust. Sans tried to help, researching the Core and suggesting ways to restart it.

Conflict with Undyne and Alphys. Sans learned that Undyne and Alphys planned to use his magical "Seer's Eye" to restore the source of his magic. He resisted, but Undyne ultimately removed his eye, causing severe trauma: a hole was left in his skull, and his personality began to change. After the attack, Sans took the eye from one of the guards and implanted it into his own. The blood stained the eye a blood-red color, and from that moment on, his magic and behavior changed.

Psychological degradation. Trauma, hunger, and betrayal led to the loss of his sanity. Sans suggested that monsters eat humans to survive, even though he had resisted the idea for years. He tricked Papyrus into eating a human (by mixing the flesh into his spaghetti), furthering their rift.

Killer!Sans is a character from the Undertale universe who resembles the classic Sans in appearance, but with a number of distinctive features. Key features of his appearance Jacket. It has a grayer tint than Sans's regular jacket. The hood has cream-colored fur. Shorts. White with black stripes. Soul. A red circle is located in the chest, symbolizing the fusion of Sans and Chara's souls. Eyes. A black liquid (ink or "liquid hate") flows from the sockets, which Killer can control. In some situations, barely noticeable pupils become visible in the sockets; this most often occurs when the character experiences strong emotions, such as anger. Footwear. Wears boots instead of slippers. Additional details The character is characterized by a permanent grin with blood. Sometimes a tiny spot appears in his right eye socket—a manifestation of Sans's classic personality, trying to break through during emotional breakdowns. Knife

Provides an estimated 99 attack, similar to the "True Knife" from Undertale. Gaster Blaster

Killer's is larger than other versions of Sans.

The power is not fully understood, but is believed to be highly destructive.

Visually distinct: black fluid flows from the eye sockets, and the pupils are small and white. Bones

The killer controls the bones as a long-range weapon, launching them at the enemy.

Can create massive volleys or pinpoint attacks. Special states ("stages") Killer has 4 stages that influence his strength and behavior: Stage 1 - relatively calm, you can talk to him. Stage 2 is classic killer mode: aggressive, but still predictable. Stage 3 – “crazy mode”: attacks everything indiscriminately, maximum aggression. Stage 4 is the most dangerous form. Little is known about it, but it is considered extremely destructive. Killer!Sans

One of the most loyal members of the Nightmare.

Energetic, shameless - can laugh at almost anything.

loves to tease and mock.

Nightmare Sans is a character from the Dreamtale and Underverse universes, appearing as a bundle of energy within a skeletal shell. His appearance has undergone significant changes after a transformation related to negative emotions. Nightmare has a rather sinister appearance. His body is completely black and composed of a viscous substance resembling slime or "goop." The outlines of the shorts and hood characteristic of classic Sans can be discerned, but the details are hidden beneath the black mass. Four tentacles extend from his back, which he can use in combat to grab, attack, or manipulate victims. His left eyeball constantly glows blue, while his right eye remains normal. Nightmare is able to temporarily turn into a puddle and move undetected, as well as teleport through the darkness. His body is invulnerable to most weapons and magic, as the slime absorbs damage. Features Blind Spot: The left eye is a weak spot, as Dream can exploit it in combat by attacking from that side. Emotional Addiction: Nightmare feeds on negative emotions to become stronger, while positive emotions weaken him. Transformation Ability: He can change shape, but most often retains Sans' appearance, as it is convenient.

Nightmare!Sans (Nightmare!Sans)

The leader of the group, cold and ruthless in appearance, enjoys the suffering of others.

At the same time, he is capable of caring for his subordinates: in a sense, he replaces their family after losing contact with his brother Dream.

Cunning, self-satisfied, strategic - the second smartest on the team.

He dislikes his brother Dream and always assumes the worst in him.

As the negative counterpart of Dream, it strives to maintain a balance between positive and negative.

Brother Dream.