I crafted something but saw no change in my combat ability! What's going on?
It’s possible the item you made is simply not strong enough to count towards your either your Attack or Defense strength. Players can only bring a limited number of each type of inventory items with them into combat. These limits are determined by the size of your Clan. If you have more of an item type than you can use in combat, your strongest items will be automatically be selected, depending on whether you are attacking or defending. This means that unless make an item whose stats are greater than the weakest item of that type you were already using, you won’t see any difference in your combat ability.

I crafted something and it made my stats decrease :( What gives?!
It sounds like you may have created an item using components that were contributing to your Attack and Defense in fights. The strength of a crafted item is not always greater than the sum of its parts.

For example, say you wanted to craft a specific item with 65 Attack. To craft this item, you require 5 component items that each have 45 Attack. If those components were contributing to your attack strength in battles, then crafting them into a single item with 65 attack would result in a net loss of attack strength, unless you replaced those components with equally strong items of the same type.

Can you tell me what I need for this Hidden Blueprint?
Us just telling you kind of defeats the purpose of “Hidden” information. However if you are looking for tips or are interested in working with other players to find an answer, you should check out the Forums or ask in World Chat :)

I crafted some items, but now I can’t find them!

Check that your inventory screen is showing the right item type, and that you don’t have any filters on your list that would exclude them from view. Also, make sure you haven’t gotten your crafting and reverse-crafting recipes mixed up. A regular crafting recipe will create a new item, while a reverse-crafting recipe breaks an item back down into components. Reverse-crafting recipes should be marked with a down-arrow.