Black arrived at the Carlton hotel pier by boat, then walked a gauntlet of 40 oversized pandas modeled after characters in the animated film, which costars Angelina Jolie. (The stunt rivaled last year's airborne arrival of Jerry Seinfeld dressed as bee.)
"It's a hard choice to decide who had the crazier stunt between me and Jerry," Black, 39, tells PEOPLE. "But I can't believe he had to come down from the top of the hotel – twice."
In fact, Black's "pandemonium" on the pier upstaged the official festival opening flick, Blindness, which stars Julianne Moore, Gael Garcia Bernal and Mark Ruffalo.
Dad-to-be Black is on his third visit to Cannes, but his mind was still stateside.
"My wife is home pregnant," he said. "I've got to get her a present. Not sure what yet, but I can't leave without getting something."
The festival in the south of France runs through May 25. This year, the jury is headed by actor Sean Penn and also includes Natalie Portman.