Here is the full list of all 20 It Takes Two achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
You did it! CO-LLA-BO-RATION!
You reached a higher state of mind. Or at least some peace and quiet.
Release that tension at the root level.
Scurvy! Ye look smashing, captain!
Again? Keep track of your kids!
Don't feed the animals! Or do, they're adorable.
Helltower? More like hello-from-up-here-tower!
Guess it was time to cash out.
Shoot for the stars, literally.
Self-inflicted paparazzi.
It takes two to… torture.
All minigames found!
They had no way out.
The truth was out there all along!
Put on a show and die trying.
Now look who's extinct!
Isn't it pretty? That's going on the fridge.
Choo Choo!
Breathe some wind into your ocarina, my skyward princess!
Took things a bit too far, didn't you?