Another long fight is going to ensue as you attempt to scale the ramp leading to the elevator. To begin with, help the Wookiees fight off the initial charge of battle droids, but be ready to task one of your soldiers to place a charge on the SBD dispenser in the middle of the ramp when the hotspot becomes available. The Wookiees should get close enough to start engaging the SBD's as they pop out, letting you save your grenades and ammo for the rest of the ramp.
After the dispenser is blown, start moving back up the ramp, chucking thermal grenades to disperse the second mass of battle droids that will have appeared. More AA ammo can be found in the cache along the rightmost wall of the ramp here, so grab it and use one or two rounds on the droidekas that appear. After the droidekas are gone, then three SBD's will likely charge out of the door behind them, so use any remaining AA ammo and EC grenades on them. Phew! It's a long fight, like we said, so you'll need to practice some ammo management if you want to have enough EC grenades and anti-armor charges to last through the whole deal.
When you reach the elevator itself, you'll need to destroy the fuel tanks across from it to reveal a pair of sniper spots; situate your soldiers in these to clear out the SBD's and battle droids before moving up to the next level.
The Final Strike
Destroy Separatist Cruiser
The time has come for you to dispatch the Separatists from Kashyyyk once and for all...or at least until Episode III hits theaters. To do so, you're going to need to take your team through the top of the spire, deposting each of them into a separate dual missile launcher. Thus, in a nice little echo of the game's first couple of missions, you'll find your squad steadily diminishing in strength, until you're left by yourself for the home stretch.
Guards!
Video Walk-through
You'll find this fight to be a lot simpler if you dispatch the Grievous guard at the beginning of it.
The first fight here is going to be among the toughest, though. Let's see, a spider droid, a Grievous guard, some droidekas, some SBD's...sounds like fun! Luckily, these guys don't all come at once, but it's still going to be a difficult fight to survive.
The spider droid is up first; you'll be able to see it immediately after you pass through the doors leading away from the elevator. If you get its attention with some blaster fire, it'll shoot up its missile scanner, so take that out with your sniper rifle, then get one of your soldiers into the snipe spot here, but instead of sending the rest of your soldiers out into the rest of the room, pack them into the same little area behind the tank here, so that they can hide from the spider droid's fire with the sniper. Soon enough, the guard will pop down from the balcony above the spider droid, and he'll be the one you want to take out first.
With all of your soldiers grouped together in one little circle, the guard should take the bait and start moving in, baton wailing. Thanks to your squadmates' super-hardiness, though, you should be able to drop an EC grenade into the middle of the crowd without damaging them too much, but it'll do a boatload of damage to the guard. You should have two EC grenades from the beginning of the level, so use them both on the guard and take it down before turning your attention back to the spider droid.
Spider Droid, Et Al
When the guard's dead, it's time to get the spider droid. With all of the positions in the room, this guy should be a routine kill. If you wish, you can use the Wookiee Rocket Launcher near the elevator to destroy the spider droid quickly, but it's far better to save it for another spider droid that'll pop up later in the level.
You'll want to have your teammates in the anti-armor and grenadier positions in the room before you polish the spider off, as doing so will trigger two droidekas and three SBD's to appear in the room behind the droid. Guess the separatists are beginning to appreciate the threat you pose to their little operations here. You'll probably also want to move the sniper over to the second anti-armor position near the door before unleashing your rockets. If everyone's in a position, though, then the droids after the spider should go down relatively quickly.
When you reach the hallway beyond the spider droid, use an EC grenade to dispatch the two droidekas, then slice the locked door; don't breach it. There are more droidekas and SBD's beyond, but you'll have a full EC grenade and AA ammo refill waiting for you at the top of the ramp, so feel free to burn through that ammo during the fight. Soon after, you'll lose Sev; he'll take off and man the first dual missile turret.
Behind Door Number Two...
Next is--guess what?--another challenging fight. When you slice through the door near Sev's turret, you'll come up behind a pair of fleeing Geonosians. Soon afterward, you'll hit anti-armor and grenadier positions. Although the sniper positions nearby look tempting, avoid them; instead, walk forward to trigger a massive influx of Geonosians, along with the appearance of a Grievous guard. With your troops in the AA and grenade positions, you should have a handle on the Geonosians, at least, but you'll want to give them a hand with the guard by pelting it with EC grenades and AA rounds of your own as it approaches your position.
When all hostiles are down, proceed cautiously out the far room; there are a pair of SBD's waiting for you. You'll lose Fixer at this point, so heal up before slicing through the next door.