Dragon Story persistent leaderboard is a recurring time based challenge between bucketed groups of players:
•  There are 6 Leagues within the Leaderboard feature which players can advance through to earn better prizes
•  Each Leaderboard challenge lasts 5 days, with a 2 day break in between
•  Players earn points by completing tasks within set time limits and reaching a Bingo
Sketch
Wireframes
Base on the product goal I was designing the user experience of the gameplay especially focus on the interaction:
•  UI Surfacing: A default HUD button and new on-board building 
•  Earning Points from Challenges
•  Leaderboard Structure
Visual design
Because there's a lot information on the main screen, I was organizing content to follow natural eye movement Z pattern. Users will know the challenge description and review their current bingo board then they can choose using boost to speedup. I chose purple as the primary color to show the contrast between UI elements and dragon leaf decor.
Iconography