See the in-game tutorial, use your mouse to dig through the ground.
Need Water is a new challenging game like the where is my water game. Dig through the ground and try to get the water (and oil) to the factories. Destroy stones and control the liquids. The water should be guided to the water factory and the oil to the oil factory. Collect the diamonds that are hidden in the earth and buy new skills and items in the upgrade panel. Unlock the achievements and earn rewards. Try to complete all the challenging levels.