Dreamtale is a Sans-centric AU created by the Tumblr user Jokublog, and connected to other AUs in that positive and negative emotions are sent from the sacred Tree of Feelings to other universes in order to maintain life. Dream and Nightmare were created as replacements when the original guardian of the tree died.
Aside from the original comic, another separate comic is currently being made.
Light being who takes the form of a skeleton. Guardian of the golden fruits, which hold positive emotions, and the more playful and vibrant of the two guardians. Despite this exterior, however, he internally suffers as much as his brother.
Light being who also takes the form of a skeleton, and guardian of the black fruits holding negative emotions. The more serious guardian who enjoys reading books given to his brother by the elders, but later on becomes a ruthless being made of pure darkness.
A homeless cat, having lost his arm and family in a fire. He becomes Dream's best friend after he shows him kindness. He later on helps him while he was stuck in stone along with the guardian of magic by taking him away from Nightmare.
The guardian of the Tree of Feelings, and Dream and Nightmare's mother. Whilst stern when needed, she's shown to be calm and patient, though she looks down on all mortal life. She died protecting her respective tree from a human who was somehow strong enough to defeat her, thus leading to the creation of the two skeletons to replace her.
The guardian of the Tree of Magic, or Yggdrasil. Her personality is unknown so far. She is the one who vows to help break the spell that turned Dream to stone, and becomes his teacher and trainer afterwards. She holds a deep hatred toward Nightmare for everything he's done.
The guardian of the Tree of Life. As of now, nothing is known about him.