Harry Osborn Was Just Low-Key Hanging
Speaking of Harry Osborn, the younger Osborn also kicked the bucket at one point in the Marvel comics. In Spectacular Spider-Man, Harry fought back the mental illness that took over his father and turned him into The Green Goblin. Harry was on the same path but he resisted enough to sacrifice himself for his friend. Flash forward to Amazing Spider-Man #546 in a story called Brand New Day, Peter and Mary Jane make a deal with the demon Mephisto to bring Aunt May back to life(she had been shot dead).Harry also miraculously returns, but reasons for his return are never explained.
