Underswap Indigo is a fusion of UT AU and fangame, which are Underswap and Undertale Yellow. Basicly a roleswap in Undertale Yellow. That means that Starlo and Ceroba swap their roles. "Morning Star", or Starlo, is a monster with such a tragic fate, due to the loss of his widow Aruma, and his student, which also was his son. Now his only goal is to fulfill Aruma's Legacy. He is strict and observant, which helps him in the fights due to his knowledge and durability.