I do not know Republic Commando, but I suspect it is a game of sorts. Basically we will play some nameless grunts from a group of clones and maybe one player will play a jedi general at best. We will roleplay how we fight our way through the clone wars and the later galactic civil wars in a rather grim scenario, since we are the expendable soldiers after all. We will most likely all survive through plot armour if you want to but you can always die and just roleplay 'yet another' clone that is your replacement.