I was playing earlier and I ran into a slave driver, much like the one you described. I was Meta Knight, he was switching out between the Star Fox crew, and the slaves were Toon Link and Marth. But this slave driver didn't target me much. When he did I simply wacked him away. After a few rounds of just watching him bully the slaves, I was getting really mad. Then he started messing with me, so I attacked him, and didn't stop untill I had killed him. The slaves interfered at first, then just stood aside. After a few rounds the slave driver switched to Snake, and ended up getting the smash ball. We were on Final D so I just flew back and forth under the stage to dodge. He got mad and started shooting, and killing, his slaves. After that they helped me beat up the slave driver, and seeing he had lost control, he left after that round. But then a party crasher came and then everyone turned on me. After a round or two of fighting them off, I got fed up with it and left. Way to thank me for liberating you.