Drump

One day, Bianca, Rosso and Nero visit the site where a dragon presumably was defeated at the Dragon Hill Ruins based on a map. Upon closer inspection of the map, Bianca notices a mysterious spade symbol and the word "DRUMP" written across the map. They find where the spade symbol is located, dig in its spot and find a mysterious object that causes a change in Rosso. What is the object, what connection does it have to dragons and what does DRUMP even mean?! (Source: MangaHelpers)