The Material Echoes

Eden is a magically rich place, and its magical nature is reflected in the two planes that share its central space in the universe. The Feywild and the Shadowfell are planes that run parallel dimensions that occupy the same cosmoligical space as Eden. They are often known as "echoes" of Eden. The landscapes mirror Eden similarly and, in places where they are completely identical (down to the molecule), Gates are created that are sources of immense power.
The Feywild, the "loud echo", is a bright and dangerous land where everything has a soul, a mind, and a heart. Nearly everything you encounter there is either alive or was created by something alive. Rather than a setting sun or moon, four orbs of light encircle the sky, shifting in color and brightness. Here is where the Seelie Court rules, and where the Unseelie hunt. This is where all fey creatures are born, though they may choose to leave this plane and live elsewhere. A plane of emotion and change, the Feywild heightens and magnifies the most obvious of your traits until you become an almost laughable caricature of yourself.
The Shadowfell, the "muted echo", is a dimly lit and slow place. It is always overcast and nearly everything is washed with a shade of grey. Everything happens slowly and deliberately in this place, including speech and thought. Non-native creatures that stay here too long become "muted" as well, gaining abilities but also developing slow thoughts. The plane of stillness and quiet, the Shadowfell attempts to sand down your rough edges and create a statue or mask of a person, devoid of all that might cause a disturbance.