Here is the full list of all 24 Cats in Time achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Korben, is that you?
Collect all postcards pieces in the game.
Find the secret level.
Collect every cat in the game.
Visit (almost) every location in the game.
Visit every period in the game.
Visit every underwater location.
Visit every Tokyo location.
Fly away!
Visit every New York location.
Found him!
Visit every wild west location.
Forge the sword.
Visit every German location.
Visit every Greek location.
Do nothing and enjoy the moment.
Visit every ancient Egypt location.
Catch some fish.
Solve level without any hints.
Wow, that was quick!
Collect all cats on one level.
Everyone needs some help.
I knew it!
Destroy everything!