Chadwick Boseman Dead: Mark Ruffalo Pens Somber Note Honoring 'Avengers' Co-Star After Death at 43

Chadwick Boseman's Marvel co-stars are beginning to reflect on the loss of the actor, who played Black Panther in four Marvel Cinematic Universe movies. Mark Ruffalo, who played Bruce Banner / The Hulk in Avengers: Infinity War and Avengers: Endgame with Boseman, called the star an "immense talent" in a heartbreaking tweet Friday night. Boseman died at age 43 from colon cancer.

"All I have to say is the tragedies amassing this year have only been made more profound by the loss of [Chadwick Boseman]," Ruffalo wrote. "What a man, and what an immense talent. Brother, you were one of the all-time greats and your greatness was only beginning. Lord love ya. Rest in power, King." Other Marvel stars shared their own tributes, including Chris Pratt, who plays Star-Lord. "This is such devastating news," Pratt wrote on Instagram. "We're praying for his family. The world has lost an immeasurable talent and a great person."

"Chadwick was someone who radiated power and peace. Who stood for so much more than himself," Brie Larson, who plays Captain Marvel, wrote in a statement on Twitter. Larson noted that Boseman "took the time to really see how you were doing and gave words of encouragement when you felt unsure." She is "honored" to have memories with Boseman. "Rest in power and peace my friend," she added.

Boseman's family said the actor died after a four-year battle with colon cancer, which he never publicly disclosed. His latest films, including Marshall, Spike Lee's Da 5 Bloods, and the upcoming Netflix adaptation of August Wilson's Ma Rainey's Black Bottom were all filmed "during and between countless" surgeries and chemotherapy, his family said.

"It was the honor of his career to bring King T'Challa to life in Black Panther," his family said. "He died in his home, with his wife and family by his side. ⁣The family thanks you for your love and prayers, and asks that you continue to respect their privacy during this difficult time."

Boseman was cast as T'Challa for 2016's Captain America: Civil War and appeared as the character in the solo Black Panther film, released in 2018. During a stop on Good Morning America, Boseman reflected on the importance of starring in the MCU's first movie centering on a Black superhero. "It was important to us, I didn't know how other people would feel about it," he said. "I knew just from the comic book what a Black Panther movie could be, the type of impact it could have, I knew it would be a revolutionary idea. I didn't necessarily know that people would buy out [the seats in] theaters."