Star Wars: Battlefront II/Revenge of the Empire

Capture the Water Fountain
This can be an extremely difficult mission. A lot depends on your proficiency with Imperial tanks and your evasion skills, as you will be fighting pretty much the largest Rebel ground force in the entire game.

Right off the bat, you are given two ITF-T tanks. Hop onto one, and drive down to the Fountain (there's actually a second route down behind the large waterfall that you can take to get down, but there's really no reason to do that here—make sure to take advantage of it in instant action battles, however). Rebel forces should be descending from the hill by this time, so leave that tank where it will block enemy infantry from moving into the fountain as much as possible (hey, every little thing helps) and start capturing the Command Post. The enemy loves to throw grenades into the water where you can't see them very well, so be alert at all times. Also, be sure to use the copious amounts of cover available and the medical and ammo droids.

Capture the Viaduct
If your original tank is still intact, take that up to the Viaduct Command Post (which actually lies below the viaduct itself); if not, a new tank will spawn near the Fountain after you capture the point. Kill the large wave of infantry that spawns near the point, trying your best to avoid Vanguard rockets and using your own to take out several enemies at once. Also, around this time you should start encountering Rebel tanks; as you probably know from the Naboo mission, these have horrible accuracy with their missile barrage ability but at close range they can still smoke you before you know what's happened. Stay a fair distance away, and use the high accuracy of your own rockets to eliminate them as quickly as possible.

When the initial wave of enemies are dead, hop off the tank and start capturing. Watch out for Rebel snipers here—they'll often hide near the Viaduct and in spots further up the hill, and the AI displays uncanny accuracy with snipers in this game. Try to jump and roll around as much as possible while capturing to make yourself harder to hit.

If you die while trying to complete this objective, respawn as either the Engineer or the Imperial Officer (which you should have unlocked by now). These classes can take some hits while still being comparatively agile. You will have to fight your way up the hill again (and this time without the tank), but because you're not in a bulky vehicle you will be able to go through the trees and use them as cover instead of going up the clearing like the first time.