Here is the full list of all 46 Fearful Symmetry & The Cursed Prince achievements worth 1,000 gamerscore.
Reach the exit in "First Steps"
Reach the exit in "Trial of Fire"
Reach the exit in "Dead-hands"
Reach the exit in "Test of Courage"
Reach the exit in "Chuckles"
Reach the exit in "Burning Feet"
Reach the exit in "Time on Hands"
Reach the exit in "Helpful Guardians"
Reach the exit in "Path of Memories"
Reach the exit in "Welcome to the Forest"
Reach the exit in "Jaws of Grass"
Reach the exit in "The Ambush"
Reach the exit in "The Willow-pit"
Reach the exit in "Tricky Bush"
Reach the exit in "The Wrathful Guardian"
Reach the exit in "Deadly Tiles"
Reach the exit in "Blue FIre Maze"
Reach the exit in "The Deadliest Trap"
Reach the exit in "The Last Guardian"
Reach the exit in "The Missing Step"
Reach the exit in "Left or Right"
Reach the exit in "Powerless"
Reach the exit in "Dodge Contest"
Reach the exit in "Keep Calm"
Complete the bonus level "Bubble Chaos".
Complete the bonus level "Mastery of Traps"
Complete the bonus level "Striped Fantasy"
Complete the bonus level "Forest on Fire"
Complete the bonus level "The Unusual Duo"
Complete the bonus level "Strategic Pruning"
Complete the bonus level "Regal Dash"
Complete the bonus level "Perspective Issue"
Complete the bonus level "Obstacles"
Complete the bonus level "One for All, All for One"
Meet with Nulan, the fire enchantress
Meet with Haim, the cursed prince.
Confront "The Last Guardian" with Hero
Confront "The Last Guardian" with Nulan
Confront "The Last Guardian" with Haim
Complete "Keep Calm"
Collect 20 treasures
Collect 40 treasures
Collect all the treasures
In what seems a sea of jaws, follow the light
Unlock all the other achievements
Reach the exit in "End of the Forest"