In build city mode you goal is to create a thriving Megalopolis! Build towers and place them wisely in the city grid to reach the goal. Increasing your city's population and level will unlock new building types. You can see the current city level and the population of the city at the top of the screen. In tower building mode you are aiming to reach a height target. The target height is shown in the lower left corner. The better you place the roof the more bonuses you will get.

You have three chances to finish the tower. If you fail, the building can still be placed in the building without a roof. After finishing a tower, use your mouse to place the building in the desired location on the city grid.