Ruffalo took part in Kimmel's annual "I Ate Your Candy" special, pretending to eat all his kids' candy and recording their reaction.
Once he told his kids, "I just ate all your candy," they attacked him. After being pummeled by his kids, he transformed into The Hulk. Watch!
After Jimmy complimented Mark on the CGI he used in the video, he joked, "Kids, I stole your residuals."
Check out some of the best videos of parents pulling the same prank on their children for the show.