Let's use Box Mode and Face Mode to create a simple skyscraper while using Mirroring to make our building quickly and efficiently.
In a new document, select a gray color swatch and tap the [B] button for Box Mode. Turn on X and Y Mirroring so everything we do is symmetrical on the ground plane.
Press and hold on the center with the Create Tool where the red grid lines appear, and drag out 7 voxels so a 14-by-14 square appears.
Switching to the Erase Tool, remove a two-by-two notch from the edges of the foundation. This will give our building a more interesting look than a perfectly flat side.
Back to the Create Tool, let's change the color to a bright orange, and set it to material #2 with a low emissive setting. Add brightly lit windows to the edges of the building. Leave the corner blank and alternate window, gap, window gap. In the notch we carved out, build a vertical two-by-two square, still leaving a 1 voxel deep notch in the side, but now we have a lit elevator shaft in the groove. Turn off X and Y Mirroring.
Select the gray material 1 swatch from the list of recently used colors and tap the F button to enable Face Mode 8. If we were to use F4, the corners would be missing when we build up the next floor, because F4 does not interact with voxels that touch diagonally on the corners, only edge to edge.
Tap the center of the foundation to add another floor. Now, switch to the Selection Tool. Press and hold on the top of the building and drag down to select the foundation beneath. Tap on the Control Point button above the Selection Tool until Clone Tool is activated.
Press and hold on the side of the building to make a copy of the selected voxels, and drag upwards to place them on top. Be careful to make sure the sides line up. If you accidentally misplace the copy, you can switch from the Clone Tool to Move Tool and adjust the position. Keep cloning the building upwards until you're happy with the height of the building.
Now press and hold on the Section Tool button to reveal the Select Menu. Drag until "Deselect All" is highlighted and release the selection. Back to the Create Tool, tap the top of the building to add one last layer over the tops of the windows. Select Erase Tool in Box Mode and turn X and Y Mirroring on again.
To create a walled terrace, start erasing from the outer corner and stop two voxels from the center so we don't erase the corner wall over the elevators. Then erase from one of the voxels behind an elevator to the other elevator in the same quadrant.
With our rooftop clear, we can make this skyscraper even taller with a second tier. From the center, Create another square with Box Mode, leaving a voxel gap between the second tier and the terrace wall. Then Erase two-by-two notches as we did on the original foundation, and create more lit windows.
Use Face Mode to Create another floor, turn off X and Y mirroring again, and Face Select to grab the new tier for Cloning. Stack upward again till it's almost as high as the first tier.
Create a top layer with Face Mode, and use Box Mode to Erase for another rooftop terrace. For the finishing touch, we can use box mode to add a gray square to begin the penthouse tier. With Face Mode, use the recent colors list to toggle between gray material 1 and orange material 2 as we Create several more layers.
And with that, we have an impressive skyscraper for a miniature city with very few operations. We can add more detail to this building by making little decorative gargoyles, or a peaked top with a warning light for airplanes. Try building a whole city with roads and parking garages.
You can follow this tutorial in video form:
Or check out the building of an entire city!