Re: Marvels biggest slap in the face!!!
If we are talking pre-MCU, I'll go with the Captain America 1979 TV movie. If you've never seen it, you only need to take a glimpse at what Cap looked like to know how awful it was.
Within the MCU- SURPRISE!- Venom's my choice. The symbiote's origin was a cliche', his dialogue was completely out of character, and he was portrayed by an emaciated goofball.
Have you seen the "Meathead Rob Lowe" Direct TV commercial? Why didn't Raimi do something like that to give Blowpher a proper Eddie Brock body?