I know what you're talking about on Geonosis. They just seemed to keep comming. At first, I tried to take that part slowly and keep near a health dispenser, but that didn't seem to work. Now, I try to sprint through that canyon, hold near the end when the droid come around the corner, and gernade the droids to take them out quickly. Basically, I try to get out of the canyon fast and move on to the next part.
That's basically what I did in the RAS level.
On Kashyyyk, I remember that that part was pretty hard. I set one person in the turret, one person on anti-armor, and one person on the SBD dispenser. I'd go around, work on the other dispenser for a little bit. If some SBD's were shooting at me, I'd take them out fast with an AA round and continue. If someone got incapacitated, I'd go heal them. The first person who was setting the detonator would finish before me, and I'd have him finish the charge on my dispenser.
For the spider droid, I'd set my squad up in AA spots and on the turret. When it first appears, I chuck a EC or two in to take out the BDs. Then I flank the spider droid and shoot him with AA or whatever I have left. It will hopefully turn towards me, and then my squad can shoot away at its backside.
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