When Marvel Studios took a gamble on casting Robert Downey Jr. as Tony Stark in 2008's Iron Man, filmmakers probably didn't anticipate the actor would become nearly as wealthy as his character. However, with the blockbuster success of the Marvel Cinematic Universe came the meteoric rise of Downey's salary package, plus back-end deals.
Source：https://www.cbr.com/robert-downey-jr-paid-mcu-films/
