The Aerialbots and Stunticons were the first two "Scramble City" combiners to be introduced in the cartoon and comic and faced off each other a few times to "advertise" the new 5-bot combiner gimmick... which is probably why some people like me think that Defensor and Bruticus were rivals, even though they were rarely on screen together (and the Protectobots were the team used the least in both the original cartoon and comic).