Trick question. You *did* complete the ancient forest. That memory is just locked away in one of your alternate personalities. You'll need someone you love to guide you through your fragmented mind and find your true self.
Are you the main character of an RPG? Because 9 times out of 10, they suffer from amnesia. This has even happened in a Star Wars RPG. --- AC Cloud: If I win, are my sins forgiven? FFVII Cloud: Not you again.
Unequip KotR materia. That thing I heard from rumors makes gamers amnesia from certain events and in this case your trip to the Ancient Forest is forgotten.
Like making them forget that they've already advised people to rush getting a KotR to help them to farm grand dragons with their disk 1 Lionheart? --- Please don't go. The drones need you. They look up to you.