Activate in the mapeditor your heights-raise-section in the panel above:
Press the number 1 on your keyboard to get a very small brush to make hills and so on.
Use 9 on the keyboard and you´ll get the largest brush to make very large hills in no time.
1-9 (numbers on your keyboard) means that with every step from 1-9 the brush to raise a hill or dig a hole is larger.
Use the left mouse button to raise a hill, the right to make it smaller.
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