Planetarium is a secret level in Swampy's Story. They player can find it by scrolling up on the Achievements page and tapping on the planet.
- Tapping the planet will result in the user unlocking the Out of this World achievement unless if the user is playing Where's My Water? Free.
- This is the only hidden level which is located in the same position in Where's My Water? and Where's My Water? Free.
- This is the only hidden level which has a Mystery Duck counterpart, Mysterious Planets.