Undertale Yellow is a turn-based role-playing game based on the popular game Undertale by Toby Fox, which is a prequel. You will play as Clover, a child who goes into Deep Cave to search for five missing people. In Deep Cave, you will meet diverse monsters who can be friends or enemies. You'll decide how to handle each encounter and track the different directions that decision leads. From unexpected allies to unexpected enemies, surprises and twists will set Clover to an ultimate fate.