Take "LOWTRICKRY"'s advise by using a hammer. Then a bigger hammer. Call in a few friends and form a tag-team match if necessary. Something will eventually give.
(Ask me sometime about left-hand threaded lug nuts on the drivers side)
"Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut