Jet trooper:I would say the jet trooper isn't that good but if you reallly want to be him here is some tips. A lot of people say that EMP should only be used for Droidekas,vehicles ect. but sometime you can get lots of kills by using it on other enemies (Highest I got without dying was 23 on ROTE)
Dark Trooper: IMO dark trooper is way better because of the Electric Gun he has. A good technique is to keep shooting with the Electric Gun untill you run out of ammo. Fly behind some cover and reload. Repeat untill you are out of ammo fly to a Ammo droid or pick up some health and repeat the process again.
I hope this helped.
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