DeletedUser
Each crafting profession creates different items that "contain an item". Example: cake (field cook), lead figurine (blacksmith). Clicking on them it pops up just like battle chests what you get, except the item inside does not go into your inventory, but in your collection cards (achievements - items - collector cards). You need to get 5 different items in order to complete 1 collection and it does not take only 5 cakes or 5 figurines. It is based on luck, like you can see in the posts above.