10. The Mask Not Going On A Killing Spree
The Mask movie sees Stanley Ipkiss get his hands on Loki's mask of mischief and he immediately becomes a likeable, light-hearted (if not slightly annoying) cartoon-like character who makes balloon animals out of thin air. In the comics, when Stanley Ipkiss first gets his hands on the mask, after exploring his new abilities, he goes on a rampage, taking revenge on personal grudges and violently killing people. There were no initial niceties. This was a massive change from the source material and dramatically changed the potential target audience of such a movie. Had the movie followed the source material more closely, it would have been a very different kettle of fish and would have been closer to the horror genre than the comedy genre that it actually ended up being a part of.