Well, if you had said "outrageous" instead of ridiculous, I would say that its Jehovah (or Jesus, I never did figure it out) killing all non-JW's at Armageddon. But under "ridiculous", I would say it's the teaching that ALL paranormal phenomena, including millions of near-death and out-of-body experiences, both adults and little children recalling vivid details of past liuves, and countless incidents of deja vu and apparations of dead loved ones, are all the work of Satan and his horde of demons who are so absolutely bored stiff and mischievous, that this is their primary reason for existence: to destroy human souls by continually playing out the ridiculous tree of knowledge fable over and over every day with every human soul on earth, as if the God of Love is going to permanently destroy anyone for being so "arrogant" as to believe that their spirit cannot be totally annihilated. Then, according to them, numerous Masters throughout history who have taught reincarnation, including Buddha, the Dalai Lama, many of the great philosophers, most of the early Church fathers, and 2/3 of the world automatically become "satanists" doomed to everlasting cutting off.
I believe, this is the epitome of, the apex of, the uber-ultimate Pharisee Judgmentalism that is the Watchtower. The amount of negative karma they are creating for themselves might set them back to the first few nanoseconds after the Big Bang.