Here is the full list of all 13 Lucid Dream achievements.
Get back your mother.
Defeat the astral worm.
Escape from the nightmare.
Find the way to change the past.
Resolve Dr. Frank's riddle.
Rescue Chiron from eternal pain.
Open the gate to the congress.
Summon Metatron.
Free the lost soul.
Find your way back to the dream.
Make deal with Oneiromancer.
Help the Moon.
Escape from the house.