Here is the full list of all 32 Knuckle Sandwich achievements.
Get an S Rank in Can I Survive this Endless Jogging Fantasy?!
Get an S Rank in Fortunate UFO Collection.
Get an S Rank in The Very Hungry Yeti.
You can do it.
Make him mad.
No wrong answers.
Hate the planet.
YEEEEEEEOOUCH!
Get an A Rank in the Cooking minigame.
3AM Challenge.
Get an A Rank in the Diner minigame.
Find Challenge Mode.
Beat the Exterminator minigame.
Beat the Space Cleaner minigame.
Beat the Dancer minigame.
Leave no stone unturned.
Gotta find 'em all.
Earn their respect.
Time for a visit.
Run into some familiar faces.
Thea.
Echo.
Dolus.
Brightside.
What are you doing?
Someone had to do it.
A chance encounter.
Beat the game in Challenge Mode.
Amazing.
I told you not to eat that!
Find every decoration for your home.
Beat the game.