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