Deltarune is filled with secret routes and hidden bosses across all of its chapters, and the third chapter of the game requires players to collect certain items to unlock the secret boss of Tenna's TV ...

To access the BONUS GAME — an alternate version of Board 1 — you’ll need to earn S-Rank on Board 1. After earning S-Rank, go to the S Door in the Board 1 Green Room. It leads to a strange backstage ...