Princess Bride homage
Princess Bride - Westley gives Vizzinni (played by Wallace Shawn) IOCANE - a (fictional) toxin, extremely poisonous.
Skip forward to 2010's Jack and the Beanstalk remake and Jack takes his computer game (C.O.W) to an Old Curiosity Shop to trade. He trades the "COW" for some magic beans; but before being offered the magic beans, the shop's owner (played by Wallace Shawn) offers Jack some IOCANE powder, before backtracking and saying "No. Too poisonous..."
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