I'm stuck on Mustafar in Rise of the Empire. Whenever I finish bringing the beacon back, I have about 13 Reinforcements (I'm a Dark Trooper) And when that Giza guy comes I get his HP down to like 20% and I get shot and I run out of reinforcements.
i finally beat it today (3rd day with battlefront and he says finally) by getting there shooting him like twice with the enginere then switching to shock trooper (best guy for every boss except jedi) and shooting him once to slam his ugly bug face into the wall
I play as a trooper. Stand on the top of the platform, so it is harder for the enemies to flank you. Then spray blaster fire at the enemies, but try to single out on the boss. It helps a lot if you have the elite rifle.
I'll also play as the Trooper and like Niner, stand on the platform by the command post next to the health droid. Elite rifle helps a great deal and he isn't too hard to spot with that big green arrow above him.