10 Secrets You Need To Know About Super Nintendo World At Universal Studios Hollywood

Once you've collected at least three keys and have entered Bowser Jr.'s Castle, there's so many fun things to see.

The walls are covered in graffiti, and there's fun photos and cool props that fans of the Super Mario franchise will love to see.

You can also find a special Bowser Jr. Block. This glowing green item is great to punch because the sound of it is Bowser Jr. laughing. Every time you hit the block, the sound changes. So, keep listening...

Also, don't forget to use your key on the treasure chest whilst you are in Jr.'s lair. You get a special stamp and a coin bonus.