Game Mode - Weekly Challenge

Introduce a "weekly challenge" on the main menu, with success criteria on pre-chosen map. Examples could include:

-Grow a District to 200 beavers [128/128 map]
-Harvest 20,000 Wood (Deliver to a pre-set drop-off point?)
-Build a District ~30 tiles above ground level
-Have 10 districts on the map during a drought (and survive!)
-Create standing water ~30 tiles above ground level
-Connect to an objective building on the other side of the map

Weekly challenges add a layer of replay to games with self-directed success criteria. Examples of other games with daily/weekly challenges/maps include:
Diablo 3 - Challenge Rifts
Monster Train - Daily Challenge
Slay the Spire - Daily Climb

This would be supplemental to the existing Hard/Normal game modes. Each challenge would be a selected criteria + map. I could imagine the first ~52 challenges (first year) being pre-seeded in the related content release, to minimize the update architecture.