The Sky Garden is a recurring area from the original game. It's accessible through the Wilderness after solving the slate puzzle and going up the One Minute Stairs.
Effects[]
The Umbrella effect can be obtained here.
Appearance[]
The Organoid stands in the background.
On the rightmost side are the three Maussan Bros watching a UFO in the nightsky. If you join them, you'll get rewarded with the "Correlations" achievement.
Next to them is a tunnel with a patch of white lilies at the end of it. Interacting with them will make the screen turn white and wake you up. You're rewarded with the "Primal" achievement.