By Maria Elena Fernandez, Times Staff Writer They don't call it the granddaddy of reality shows for nothing. "Survivor" returns to the CBS line-up on Feb. 11 with its 20th cycle, another "All-Stars" season that is sure to get our island juices flowing. As if he was reading our fanboy/girl minds, executive producer Mark Burnett teamed up our favorite heroes and villains for what could be the biggest "Survivor" showdown we've ever seen. If you're not sure about the potential, think " Samoa's" Russell on the same side as "Coach," our friendly neighborhood dragon slayer. What else could we possibly want in reality TV? Here's a look at who's playing for the good guys and who's playing for the bad guys. Can we really be sure who's who?