On the Bowser’s Fury side of Super Mario 3D World + Bowser’s Fury, you are tasked with finding Cat Shines in a similar way that you might find Stars, Shine Sprites, or Moons in past Super Mario 3D games. Some of these Cat Shines are easier to find than others, though, with well-hidden objectives and mandatory abilities needing to be used in certain areas. On Pounce Bounce Isle, there is a tantalizingly close Cat Shine you can see in a cage after you find a couple of the collectibles here. Here is how to complete Key to the Cat Shine on Pounce Bounce Isle in Super Mario 3D World + Bowser’s Fury.
First, before you can have the chance to complete this event, you will need to complete the Make the Lighthouse Shine and Hurry! Jump High, Jump Fast quests on this island. Upon returning to the island after finishing those two, you will notice the cage we need to unlock.
There is no secret or tricks about this quest. You merely need to find the key on the island and return it to the cage. However, there are only two ways to get the key. You will need either the Catsuit power-up or a Propeller Block from the Question Blocks near the cage.
With either of those equipped, make your way to the part of the island with the big wall and the bullet bill cannon on top. Either climb or fly to the top of the other edge of the wall, and you will see the key you need.
Return the key to the cage at the beginning of the island, and you will be rewarded with yet another Cat Shine.