In brief: It’s been over three years since The Witcher 3: Wild Hunt was released. Being one of the best RPGs, and games, ever made, most people have poured hundreds of hours into CD Projekt’s title, but there are some Easter eggs many players still don’t know about, including the ghost ship that only appears briefly once each day.

To celebrate the 11-year anniversary of the original Witcher’s launch, the games’ official Twitter account is revealing a little-known fact about the series every day for eleven days. The first was the concept art that led to the creation of sorceress Triss Merigold’s outfit from the Witcher 3.

The second Witcher fact reveals the third game’s ghost ship. While articles that reveal the vessel and how to find it have been around for years, this was the first time many players became aware of the ship. Even people who’d been playing for over 1000 hours didn’t know it was in the game.

For those who want to seek out the ghostly apparition, head to the small islands between An Skellig and Hindarsfjall on the Skellige map. It usually appears just after 1 AM game time for a brief moment. While the ship doesn’t actually do anything other than rising from and falling beneath the water, it’s pretty cool to see in person, as it were.

While the final expansion for Witcher 3—Blood and Wine—came out in May 2016, the franchise is as popular as ever right now. Excitement is building for the upcoming Netflix TV series, which sees Henry Cavill take on the role of Geralt, while the standalone Gwent-themed RPG Thronebreaker arrives next week.