Ancestral Key

The Ancestral Key is a key that opens the locked room in the cave behind Twinsen's house.

This key was passed throughout the generations at the Heir's family, until an ancestor of the family name Hégésippe was attacked and killed by the pirate LeBorgne while possessing the key. LeBorgne kept the key with him until the day he died, and eventually hid it somewhere among his treasure. However, until the days of FunFrock's reign, no one had any idea where the treasure was, as LeBorgne's log book was lost. Due to that, many people were looking for LeBorgne's lost treasure. The story of the key's loss is described in details in a sign outside the room.

After finding the Book of Bù in the Temple of Bù, Twinsen hears from the old hermit outside the temple that his family must have left information for him in his house. Twinsen goes to his house, where he finds the secret cave near it. Reading the sign outside the locked room, Twinsen understands that he has to find LeBorgne's lost treasure, and thus starts asking most of the characters he meets for information regarding LeBorgne.

Eventually, Twinsen reaches Maritime Museum in Proxima Island. By getting the museum shut and then sneaking into it, Twinsen is able to steal the Ancestral Key from LeBorgne's chest.

Twinsen then goes back to his house, and opens the locked room with the key. Inside, he finds Gawley's Horn and Sendell's Medallion, as well as a sign telling him about the locations of the three Runic Stones around the planet.