Commander! Our troops have restored the old Submarine. Starting from HQ 9 you can discover underwater treasures with it. Look for dive locations on your map, and send the Submarine on missions!
Dive locations appear randomly and you can also find them by exploring new areas of the map. The first one will appear when you've fully explored all of your Radar level 7 zones. Each dive location will give you several diving targets to chose from. Pick your targets carefully as you cannot retrieve all the treasures from a location! What will your troops bring back to base? Diamonds? Resources? Or maybe Power Stones?
You can also upgrade the submarine for deeper dives that yield greater rewards
Check out this tutorial video and find out how to send your Submarine on a deep sea treasure hunt!