Dream san

Dream was created from the light expelled by the Dream Tree, better known as the Tree of Emotions. Although he is Sans, it's more accurate to call him Dream, named after the Tree that gave him life. Dream originally had neither a monster nor a human soul, but when his brother Nightmare destroyed the Tree of Emotions and consumed all the spoiled apples, Dream consumed the last golden apple, which became his soul and made him mortal.

As Joku stated, he, Nightmare, and Dream all share the same birthday: December 21st. December 21st is the last day of the Sagittarius zodiac sign. This makes both Dream and Nightmare Sagittarius. Dream constantly travels through the multiverse because he needs to spread positive emotions throughout the universes. This is also due to the fact that, unlike Nightmare, Dream's aura is very weak and cannot reach every universe. Dream isn't as kind and pure as the fandom portrays him; he's actually quite selfish. This is revealed by the fact that when his former brother Nightmare lived with him in Dreamtale, Dream constantly broke the gifts from the residents intended for his brother because they were worthless. Dream created and invented gifts himself so that Nightmare would think the residents of their universe appreciated him. The guardian of the golden, luminous, or sleep-inducing fruit/apple, created by the Tree of Emotions. If he touches the dark fruits, they turn golden, transforming from negative energy into positive. However, he cannot touch Nightmare, as the substance of the latter is equivalent to corrosive acid for Dream, and being near him is dangerous for Dream, as his brother's aura is much stronger and repels any positive emotions. Also, Dream, unlike Nightmare, would never eat all the apples [5]. His mother (like Nightmare's) is the spirit of the Tree of Emotions. When he is overly impressed, his pupils turn into stars. He is not originally a skeleton, just like his brother. Before the incident in Dreamtale, he had no soul. But he had to consume the last golden apple to preserve all the positive feelings from Nightmare. Along with his newfound abilities, he gained vulnerability. Dream and Ink were friends for a while, but due to their differing worldviews[6], they drifted apart (Ink doesn't care what happens in universes unless they are interfered with, while Dream cares about the feelings of the universe's inhabitants). Nevertheless, they aren't enemies. Dream respects Error because he knows that if he doesn't maintain the AU balance, everyone will die.

Dream is shorter than the original Sans. He wears a golden crown on his head and a blue jacket, with slightly darker trousers. The jacket is fastened with a golden belt bearing the initials "DS" (Dream Sans). The belt has spheres on the sides containing everyone's hopes and dreams. He has boots that match his belt, and he also wears a golden cloak, a gift from his brother, fastened with a clasp.

His second outfit consists of a black suit with black gloves, over which he wears regular yellow gloves and yellow boots on green ribbons. A yellow cape/vest. His scarf with a sun design is on the back of his neck, the last remnants of his former cape, which Nightmare tore. There are two ribbons with sun images on the back, and a pink star-shaped badge is attached to the front. The belt with the initials "DS" is now green.

As the embodiment of positive emotions, Dream can absorb positive emotions from his surroundings and use them to heal himself or his companions, although this consumes a lot of energy; he can also use them to increase his speed and strength, although his physical strength is already great, allowing him to lift entire boulders[3]. His weapons[4] are a golden staff with stars on the ends and a golden bow that shoots energy arrows consisting of the same emotions. These arrows are one of the few weapons capable of harming Nightmare. His bow can also be split into two daggers connected by a bowstring, but he only uses this in extreme cases. Dream can only travel to universes where there are positive emotions. He can also use his staff to create a barrier.

Dream himself is immortal in the physical sense, but while in an AU where only negative emotions exist, Dream will begin to lose strength and may die if he stays there for a long time.

Dream's childish behavior is a result of his imprisonment in stone for 494 years. He essentially missed the entire stage of adulthood, which is why he remains young in character and knowledge. His soul is a wellspring of positive emotions, making him incapable of hatred towards anyone (even his brother). However, this doesn't negate the fact that he is capable of experiencing other negative emotions, like any other living being. Because Dream was imprisoned in stone, though unconscious, he still felt the emotions of all the inhabitants of the multiverse, and over 494 years of imprisonment, he absorbed a significant amount of negativity, much of it stemming from his brother. This has led to some mild psychological trauma, as he regrets his inability to help anyone during those centuries.

In any universe that Dream doesn't belong to, he will try to fit in as much as possible [2].