What can change the shape of a landform?
The shape of a landform can be altered by natural events such as earthquakes, tsunamis, landslides, volcanic eruptions, etc. Each of these acts could be violent enough to completely destroy everything present on the landform and remove even the soil and the organic matter (let alone the flora and fauna of the region).
Lets look at some of them more closely. Volcanic eruptions release the heat of the earth's interior in the form of molten rocks (called lava) and gases. Such violent eruptions of high temperature material melts most of the substances in its path and deposits on the surface of the land. Over time, the hot material cools down and forms a new surface. Tsunamis are high-speed, tall waves that can hit a coastal area and destroy everything in their path, clearing out the landform.
Hope this helps.