Avengers (1963) #125-126 l 54

Thanks to some girl who knows Rick Jones, the Avengers get caught up in an intergalactic war with Thanos. We end the issue with the gray-skinned alien hiding out on the mansion's roof. Then Klaw and Solarr try to trick Black Panther into giving up his country. It goes so badly that T'Challa quits the team out of shame.