The position of the sun through out the day?
The Earth's rotation changes the angle of the sun as the day passes, so the shadows change based on the position of the sun in the sky. If the sun is up high (around noon), the shadows will be short or not appear to exist (they are under or nearly under the objects). As it gets later in the day, the shadows get longer.
when you change the object that creates the shadow by blocking the light, its' shadow will change. or there is another light source shining from a different direction on the object will affect the shadow too.
the position of the sun
The moon's shadow changes its placement due to the moon's orbit around the Earth and the Earth's rotation on its axis. This movement causes the moon's shadow to shift and change its position relative to the Earth.
when you move and when the sun angle changes
The shadow is caused by the earth blocking the path of the light from the sun casting shadow on the moon. When the earth is not in between the sun and the moon then we have a "full moon."
it is not a shadow
the object blocking the light or the light source are moved or changed. A shadow is created when an object is placed in the path of light. If the object remains unchanged then the movement of the light that is casting the shadow will alter the shape.
lunar eclipse
i think you know it
The shadow is caused by the light of the sun.
the sun
You cannot change sonic into shadow in super smash bros brawl