Thanks for making this game! I enjoyed the educational and historical content.
1. English translation is very confusing in places - I finally figured out that a "buckets wheel" is a new blue card that is created after you build a red-card "bucket wheel" and that you combine "buckets wheel" with "water wheel" to make a "Water-work."
2. Is there a help page with card costs listed (even if only for discovered cards)? Sometimes the entire 40-card deck doesn't have enough (say Building Materials or Craftsmen) to build, and by committing to a particular structure (or discarding poorly) you end up wasting 8+ turns.
3. Is there a reason that Wells (+2 water) forever block you from building Sumps (+5-10)? I would assume that Wells could be capped (trashed) and overwritten with a Sump, or even both that could be built in the same place.