Gold Horns Trophy in White Knight Chronicles
Slay 10,000 monsters. A trophy in the shape of a dragon god's horn.
How to unlock Gold Horns
Again, you do not need to do anything in order to get this trophy. 10,000 is a lot of monsters but you will be killing a lot more than this in order to get your platinum. This should come naturally at about Guild Rank 9 or 10.