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.
Find the secret level.
Korben, is that you?
Fly away!
Collect every cat in the game.
Visit every underwater location.
Collect all postcards pieces in the game.
Visit every Tokyo location.
Visit every New York location.
Visit every wild west location.
Forge the sword.
Visit every German location.
Visit every Greek location.
Visit (almost) every location in the game.
Visit every period in the game.
Found him!
Visit every ancient Egypt location.
Everyone needs some help.
Catch some fish.
Solve level without any hints.
Wow, that was quick!
I knew it!
Do nothing and enjoy the moment.
Collect all cats on one level.
Destroy everything!