How do you use and fill the treasure chest piece

Answer from: NiceGuy1
I think you're talking about the Dragon Treasure Chest, or Hidden Treasure, that comes in the Pirate Seas Adventure Pack? Go to a level, and you generally want to put it on the portal right at the beginning. While it's working you'll hear a "ping" sound, kind of like a submarine sonar. You'll see the icon appear at the bottom of your screen. When you get a little close to the hidden treasure chest, you'll get one green ring around the icon. Two when you're closer, 3 when you're basically on top of it. When you are on top of it, it will pop up from the ground, open it like any other treasure chest. As I recall there are 4 on each level (you can only find one per playthrough, so you have to restart the level if you want to find another), when you find them all Eon will immediately tell you "This item has run out of power for this level" when you put it on the portal. Note that these chests count towards the number of chests you've found on the level, so you might want to find all the normal chests first to make sure you don't miss one without knowing it. :)