Here is the full list of all 29 Dream achievements.
Finish the graveyard puzzle in ten moves or less.
Play the first bar of 'Counting Sheep'.
Leave on all the lights before sleeping.
Show off your festive side.
Finish Act One's Nightmare.
Finish Act One.
Find the memories of an old experiment.
Find a past project.
Epic support needed...
Finish Act Two.
Finish Act Three.
Finish Act Two's Nightmare.
Finish Act Three's Nightmare.
Collect all the Dream bible pages.
Visit all the side dreams.
Find the mess on floor one.
Finish all four mazes without getting caught.
Eat all the cupcakes.