Here is the full list of all 17 Noclipped achievements.
Play Sandbox more at least once
Stare at the floor for 20 minutes
Pick up carpet mushrooms
No-clip out of reality and enter level 0
Get killed by the rare OwO smiler
Find a computer and click on the keyboard 50 times or more
Die for the first time
Kill 1 entity
Kill 10 entities
Kill 25 entities
Kill 50 entities
Kill 100 entities
Craft your first weapon
Parry an entity attack for the first time
Reach 0 sanity
Pick up firesalt
Explore all of the levels available in chapter 1