paid tribute, saying he continued to work ‘between countless surgeries and chemotherapy’ and called him ‘a true fighter.’Chadwick’s Avengers co-star Mark Ruffalo was among the first to pay tribute to the actor, writing on Twitter: ‘All I have to say is the tragedies amassing this year have only been made more profound by the loss of #Chadwickboseman. What a man, and what an immense talent.