How I Got Rid of this Beast
Strangely enough, I got it to go away. I did this by drawing it and coming up with ideas of how to escape from it.
The weakness of this beast is that it only has 3 toes per paw; because of that it has balance problems. I told myself that I could escape from him because of his imbalance; and since my mind believed it, I did escape.
Also, the drawing that I made was less intimidating than the actual monster. This may have helped my mind decrease my fear, because the new (less scary) monster replaced him.
I am curious if these approaches help with visual hallucinations of your own.