Mars Warning: If you have not reached the end of the VF Campaign Map, do not enter Space Age Mars tech tree. You will not be able to make Mars goods until you battle on the locked Mars Campaign Map. This means you will quickly get Tech Locked and will not be able to make any Mars units, either.
Well, you can make Mars goods using Event Goods buildings like The Ship, the Pagodas, Sleigh Builders, et cetra, but, you cannot make the 6th Mars good (Mars Ore) until you fight the SAMars Campaign Map.
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If we are to test SAMars, Betans will need early access to the Mars Campaign Map. Otherwise, given my track record on Camapign Age maps, I will need Mars units to finish the last few VF provinces so, I could spend many months stuck at the beginning of SAMars before I can get Mars Ore using GE won SAM units. Hopefully, I can start SAM Campaign map before Years End.