To add crew to your Harvesters in Dune: Spice wars, you need at least 50 Manpower. You can get Manpower by building military buildings that produce it, like the Harkon Recruitment Office. Each building will add 4 Manpower as time goes on. If you want more Manpower, we recommend building more structures that produce it.
You can also get more Manpower in Dune: Spice Wars by researching certain tech in the Development tab. Once you have 50 Manpower, you can manually add more crew to your Harvester. To add more crew, click on your Harvester and find the button shown below. Clicking the button in the image above will add one crew to your Harvester. You can add up to three and sometimes four with specific tech research. You will also improve the Spice production for every crew you add to Harvesters.
What this translates to is more Spice added to the Spice stockpile. The Spice you add to the Stockpile can also be used to gain more Solari by moving the Stockpile slider down. Moving the slider down will add more Spice to Choam deals, which will give you more Solari. Because of this, we recommend adding crew to your Harvesters whenever possible, as you will need Solari (the main currency in the game) to run your Empire.
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