Total Nerd

The Most Ruthless Characters In The Marvel Cinematic Universe, Ranked

List Rules
Vote up the most cold-blooded characters to populate the MCU.

Marvel Studios may be owned by Disney, but the MCU is far from G-rated. There are a lot of dark themes and characters in the series, and some of those characters are downright ruthless. It's not just the villains either - even some of the most popular heroes in the MCU can be brutal. Thor arms himself with a hammer, after all, which requires extreme action in a fight. 

The MCU is clearly full of people willing to make hard decisions - but which MCU characters are the most ruthless? Is it worse to extinguish half of all life without hesitation, or to take out a single person in a particularly cruel way? What qualifies as ruthless, and who meets those qualifications best?