Deep in the Martian canyons there are places suitable for farming. As water fills out the deep places, we’re gonna need good old dams to keep our plantations safe. Ever dreamed of life in the country side – well, here it is…
There is no requirement for playing this card. After all, building a dam before the water arrives is a smart move, and keeping some of the deepest parts of Mars dry may prove to be lucrative when the tourists start arriving. When you play this card, paying 23 M€, you get 2 production of M€. You also get to place a greenery tile, thereby raising the oxygen level by increasing photosynthesis. But, as you can see, there is an asterisk over the tile icon. This means that there is a special rule applied to the symbol, written with capital letters in the explaining parenthesis. In this case, the greenery tile must be placed on an area reserved for ocean. That might intervene with your competitors’ plans, but I believe that’s the general idea.