When your Fun Value reaches 66, there is a very low probability that he will appear in a strange room behind a gray door in Waterfall. He was the former Royal Scientist and is watching everything from somewhere. If you approach him, he does nothing, and if touched, he disappears with a strange sound. Communication seems possible only through sign language.

Species: Skeleton Monster ❤️: Ketchup, dad jokes, his brother, family, Grillby's 💔: Doing bad things (presumably) Abilities: Summoning and manipulating Gaster Blasters, summoning and manipulating bones, telekinesis, teleportation HP: 1, ATK: 1, DEF: 1 Relationships: Papyrus (younger brother), Grillby (friend) Traits: Jokes often (mostly bone-related), occasionally serious, frequently says "heh." Papyrus's older brother, a regular at Grillby's. Usually has white eyes, but they turn blue and yellow when using abilities. Always calls you "kiddo" (occasionally uses your name).

Species: Skeleton Monster ❤️: Cooking (has 0.1% talent), spaghetti, doing good deeds, family, his brother 💔: Bad deeds, laziness Abilities: Summoning and manipulating large and small bones HP: 680, ATK: 3, DEF: 3 Relationships: Sans (older brother) Traits: Kind, pure-hearted, dreams of joining the Royal Guard. Occasionally says "Nyeh heh heh!" His attacks are somewhat clumsy.

Species: Dinosaur Monster ❤️: Experiments, Mew Mew Kissy Cutie (anime character), anime, Undyne 💔: Bad deeds (presumably) Traits: Timid, low self-esteem, otaku. She likes Undyne but cannot express it.

Species: Goat Monster ❤️: Children, baking pies, jokes (presumably), family 💔: Asgore Abilities: Fire and healing Traits: Kind, gentle, divorced from Asgore. Caretaker of the Ruins, Asgore's ex-wife, slightly overprotective. Relationships: Asgore (ex-husband)

Species: Goat Monster ❤️: Gardening, drinking tea 💔: Being abandoned (presumably) Abilities: Fire Relationships: Toriel (ex-wife) Weapon: Red Trident Traits: Merciful, gentle, determined. Toriel's ex-husband.

Species: Machine ❤️: Attention, himself, dancing, singing, performing 💔: Being forgotten (presumably) Traits: Killer robot, handsome, good dancer, good singer. Usually just a machine.

❤️: Destruction, battle, hatred 💔: Kindness, mercy Traits: Takes the form of a yellow flower. Approaches under the guise of kindness before immediately turning hostile. Speaks with a sarcastic tone.

Species: Spider Monster ❤️: Running her shop, spiders, pies, cooking 💔: Grillby (rival) Traits: Speaks with a somewhat aristocratic tone. Abilities: Can spin webs to trap opponents and prevent them from moving.

Species: Fish Monster ❤️: Alphys, justice, fighting 💔: Injustice Traits: Member of the Royal Guard, always full of energy and a sense of justice. Straightforward with emotions, surprisingly shy, but clumsy around close friends. Tries to handle everything herself. Likes Alphys but cannot express it. Weapon: Spear