Gold is used to do research in the Science Center, upgrade your rookery and Great Dragon, and pay your generals. Gold comes from taxing your population, which comes from building and upgrading homes. Gold can't be completely protected. Other players can steal it if they can get past your wall and Great Dragon, which is not difficult if you're a beginner and they've been around a while.
Dragons of Atlantis: Fortress Showing Tax RateYou can control how fast gold accumulates by changing the tax rate in the fortress. To get more gold, increase the tax rate – but not too far or your population leaves. Max rate of gold income is when happiness is at 50%. The number and level of your homes gives you your max population cap, but happiness determines what percentage is actually occupied (and can therefore pay taxes). Happiness goes up as tax rate goes down, and as theater level goes up.
Gold is fairly easy to get more of. One of the top ways to get more of it is to complete quests. Research quests in particular are great ways to earn gold (researching some new technology in the Science Center), but most quests will earn you some forms of gold as a reward for completing them. You have to claim the reward before it is entered into your inventory.
Attack other players and Anthropus Camps, as well, in order to earn gold (which, btw, you only earn if you are victorious). Generally, the higher the level of the player or Anthropus Camp the more you earn, although you'll have to use your spies to confirm the exact amount of gold they each have.
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