The Shiny Amulet DLC contain :

The Shiny Amulet in-game item that boost the player chance to find a shining monster!
The rate goes from 1/500 to 1/250!

The original Game Trailer featured on Steam...

• 8 Pieces of Artwork in both PNG & PDF format that include :
  
• The Complete Map...
  
• 4 Wallpapers, one for cellphone and the other three for PC...
  
• The Game Cover, the Game Logo and the Game Icon...

This DLC is included in the Deluxe Edition Bundle too...

To find the bonus content, locate the Steam Apps folder, open it and locate the Common folder, open it. Locate the game folder and all this content will be within the Bonus Content folder...

*If you have any problem installing this DLC uninstall the game and reinstall it at the same time as the DLC, it should fix it.*