I dare you…
A challenge is a page created to request/goad other wikizens to create something specific. The nature of challenges can vary greatly. Some might be requests for resolution of a sticky problem. Others might request specific NPCs, artifacts, or charms. Some might even be things like "find that page reference".
New pages are created for each challenge, all as subpages of "Challenge". In many cases, responses to the challenge will be entered into the page issuing the challenge. In cases where the challenge is to create content like an artifact or charm, you should create responses as normal artifacts, charms, etc., but reference the challenge it is meant to answer in the text of the item and edit the challenge page to link to the new item.
Often, there will be no "right answer" to a challenge. The idea is mainly to spur involvement and creativity.
- Suzume's Wyld-stuff Challenge Thingie