Welcome to this list, here you can vote for your favorite Undertale characters! Let's start the count !!
Catty / Bratty
They are a couple of vendors that can be found at MTT Resort. They are best friends, and they usually talk synchronously at the same time, despite their differences they are very close and share the same love for Mettaton. They are believed to be close friends of Alphys
He is an employee of MTT-Brand Burger Emporium.
Nice Cream Guy
Dogamy and Dogaressa
Alphys is a "nerdy", shy and somewhat lonely who loves anime and comics. He often begins to stutter and seems to have developed a great admiration for the human after having seen him through the cameras around the entire Underground. She has a hidden side of herself full of guilt, fear and insecurities of her and her accomplishments. He has romantic feelings for Undyne and Asgore. She is the Real Scientist, since she reached by creating a robot with a soul. (Mettaton)
He is a yellow boy, with a tail and thorns behind his head. He has no arms and wears a striped sweater. His role model is Undyne, he is very innocent and assumes a very energetic and clumsy personality
Asgore Dreemurr is the ruler of the Subsoil, and of all its inhabitants, the monsters. He is Toriel's ex-husband and Asriel's biological father. Asgore starts being kind and gentle, but when he's in combat he looks like he's a demon. He is represented as a kind and tolerant family man. The moment the protagonist fights against him, he is aware of the horrible things he did to try to save his people, and simply lowers his head in shame, while he fights. He wears armor, as well as a blue cape, and some yellow shoulder pads. Wear a small crown that you wear on your head. And a great red trident in his battle sprite.
Temmie is a kind of monster found in the Undertale game as a "special enemy" in the Waterfall, a resident of the village of Temmie or the owner of the Tem Store or "Tem Shop" The Temmies resemble a cat with ears of dog along with its cat ears set, black or gray hair up to the shoulders, white skin and is wearing a light blue top with yellow stripes. She seems to be extremely happy and very distracted but if you try to make conversation with her she will show her different facets. It is very expressive, loud and easily surprised.
Muffet is a purple-skinned spider-monster, five eyes and six arms. She is dressed in a red dress with pants in the lower area, buttons on the front, a red ribbon on the chest and two more ribbons on her hair. Muffet appears as the leader of the spiders in the Underground, which is making its own food sale, where each item costs 9999 gold, in Hotland.
WD Gaster is a hidden character in Undertale. If the game is played normally, its existence will be hidden, and only characters like the River Person will mention it. During the history of Undertale, the player may discover that Gaster was the real scientist before Alphys. It is assumed that he was erased from material existence, but his consciousness is still present, forced to understand that the world is the same without him. WD Gaster does not have a known official appearance, but in the game there are two potential possibilities, which were planned to appear in Waterfall. He is said to be the father of Papyrus and Sans but this is not 100% confirmed
Flowey is the first character you meet and talk at the beginning of Undertale. Tends to call everyone an idiot. Flowey appears as a large flower with 6 yellow petals around its head. Your face changes dramatically depending on your emotions. Sometimes it is shown with leaves. Flowey has a cheerful expression, but can quickly alter it depending on his emotions. At first, he introduces himself as someone kind and friendly. He has a habit of calling himself "your best friend" and, as his father uses polite words like "caramba" at the end of his sentences. As shown throughout the game, Flowey possesses a malevolent and cruel character, constantly reprimanding the protagonist for ignoring his advice to "kill or die" Despite all his cruelty and, usually, evil actions, it is implied that Flowey See the protagonist almost as a friend.
Napstablook is a melancholic monster, ghost and musician who lives in Waterfall. He has low self-esteem, an introverted attitude and suffers from depression. Despite this, he proved to be courteous to others. He creates his own music. His cousin is Mettaton
Mettaton is a confident and captivating television host, lover of drama, action and violence. He lives for his audience ratings and loves acting. Sometimes it shows a weak appreciation of existence, as mentioned in several neutral endings. The initial appearance of Mettaton shows it as a gray rectangular box with a grid of lights on the top, which can change color depending on its various actions, Having activated the switch on its back in the neutral or pacifist path, Mettaton will be transformed into Mettaton EX, a new body that Alphys created for him at his special request. In this humanoid form, he has a dark hair with a bangs covering his right eye, pale "skin" and visible metal parts above and below his left eye. After the player faces him on the genocidal route, Mettaton will be transformed into Mettaton NEO, a form very similar to Mettaton EX, but obviously with a more combat-oriented design.
Asriel Dreemurr is the prince of the monsters: the biological son of Queen Toriel and King Asgore, the adoptive brother of Chara, and the true identity of Flowey. Asriel takes on the appearance of a humanoid goat or possibly a type of dragon that has no hooves, similar to its parents. Asriel "was a bit crying", somewhat fearful and docile, a kind and loving child who loved jokes and jokes. Unfortunately, a laboratory experiment brings him back to life without his soul, making him the heartless flower, Flowey. Asriel begins to torment the monsters around him for sport, since he is unable to see the joy even in seeing his parents happy.
Undyne has an intensely passionate personality. She is strong and confident. She has a competitive spirit, but ultimately she is close to those she considers friends. She is the only monster known to possess natural Determination apart from the boss monsters, although in much smaller quantities that allow their souls to persist after death. She initially appears as an imposing titan in a black and white menacing armor suit. She is incredibly powerful, as evidenced by her ability to break rocks with just punches.
Toriel is a Chief Monster, one of the main characters of Undertale, she is the Guardian of the Ruins, ex-wife of Asgore and biological mother of Asriel. Toriel is a very kind and maternal monster who really cares about the player and his well-being. He also has a tough personality. Toriel enjoys cooking. She is also able to bake other things quite well, as shown when she bakes a cinnamon-caramel cake for herself and the player. Toriel has always wanted to be a teacher. This is also illustrated in the credits of the game at the end of the True Pacifist Route, when she is standing in front of a school where she is a teacher or principal.
Frisk is the playable character, whose name is only revealed at the end of the Pacifist Route. He is one of the eight humans who reach the Underworld through Mount Ebott. Undertale documents Frisk's trip in the Underground to Asgore Castle, where the barrier to escape is located. Frisk appears to be a silent person, with few things to say. He is the good character and his bad counterpart is Chara. It should be noted that Frisk is a "silent protagonist", designed for players to put themselves in their shoes. Therefore, his personality is never completely defined within the game, and it is the player's job to fill that void.
Papyrus is a tall skeleton, perhaps anatomically incorrect, with a more straight and geometric skull structure (in contrast to his brother's skull that is rounder). Papyrus is a noisy and extravagant skeleton that shows a safe and charismatic image of himself. It tends to be hardworking and despite its strong personality, it is a skeleton with a good heart. He is extremely optimistic and innocent. Papyrus is occasionally unconscious and not observant. He really likes spaghetti and cooks it in his spare time, although many characters seem to think that he is not so good at it. He usually says nyeh heh heh!
Sans is a skeleton of short stature and large bones, dressed in a hoodie or jacket, unbuttoned at all times, with white shirt, black shorts and tennis shoes. He is always seen with a smile and barely moves the corners of his mouth. He has white pupils that tend to disappear when he speaks in a serious tone. Sans is shown with a very relaxed personality, sleeping at work or taking breaks constantly. Enjoy making bad puns related to skeletons, to the displeasure of his brother. It is of a good and comforting nature, but it becomes sinisterly serious in abrupt moments. It is extremely observant, its lines and actions are the ones that change the most throughout the game depending on the choices made