You first need to play New York Advanced mode and find the 12 hidden special cats.




Every time you find one, you'll get a special card, unique for that cat.




If you look at the bottom of the card, you'll see it tells you which two special cats you need to find to unlock which bonus level.




Now that I found the two special cats needed for this specific bonus level, a message pops up confirming as much.




Once you find all 12 special cats, you will unlock all six bonus levels.




Important: To see the tiny fur balls clearer, you may enlarge any picture in this guide by left-clicking on it then once more on the semi-enlarged copy that shows up.

Ninja Cats HQ - B&W [1/2] Right side




Ninja Cats HQ - B&W [2/2] Left side
Last cat is below the video game, behind the poster on the wall. Please check the Colored version.




Ninja Cats HQ - Colored [1/2] Right side




Ninja Cats HQ - Colored [2/2] Left side

Roof Top - B&W [1/2] Right side




Roof Top - B&W [1/2] Right side




Roof Top - Colored [1/2] Right side




Roof Top - Colored [2/2] Left side

Smelly Cat Café - B&W [1/2] Right side




Smelly Cat Café - B&W [2/2] Left side




Smelly Cat Café - Colored [1/2] Right side




Smelly Cat Café - Colored [2/2] Left side

Metro - B&W [1/3] Top




Metro - B&W [2/3] Middle




Metro - B&W [3/3] Bottom




Metro - Colored [1/3] Top




Metro - Colored [2/3] Middle




Metro - Colored [3/3] Bottom

Museum - B&W [1/4] Top-right




Museum - B&W [2/4] Bottom-right




Museum - B&W [3/4] Top-left




Museum - B&W [4/4] Bottom-left




Museum - Colored [1/4] Top-right




Museum - Colored [2/4] Bottom-right




Museum - Colored [3/4] Top-Left




Museum - Colored [4/4] Bottom-Left

City's Park - B&W [1/4] Far-right




City's Park - B&W [2/4] Second to right




City's Park - B&W [3/4] Second to left




City's Park - B&W [4/4] Far left




City's Park - Colored [1/4] Far-right




City's Park - Colored [2/4] Second from the right




City's Park - Colored [3/4] Second from the left




City's Park - Colored [4/4] Far Left

Now you've completed all six bonus levels, you have unlocked the corresponding six achievements.

By completing each of these at least once, you have also found a total of 425 hidden cats. This will definitely help you progress to get even more achievements, like Find 700 cats.



You need a total of 850 to unlock the highest achievement.

This is my third hidden cats game and I thought maybe this guide might help others! Much love to you!