How to make money?

Yes, you can earn money in this game, yes, you can do it without spending a penny of your own funds.
However, there are ways to earn money that involve investments.

Ways to make money that don't require any investment

1) By exploring the world you can find coins. Sometimes you will get from 1 to 5 coins.
2) The referral program will let you earn a percentage of all coins spent by the players you bring in.
3) Mining at gold mines - passive earnings from extracting coins. For higher speed, hire engineers.
Everything earned can be converted and withdrawn into cryptocurrency.

Ways to make money that imply having coins (deposited to the balance or earned in the game)

1) Opening wooden, silver and gold hexes - underneath them you can find more serious treasures - up to 9000 coins.
2) Building wooden and gold hexes - you need to build a specific hex by its number in order to receive a reward many times the cost of construction.