IIRC Nemesis 3 has no bonuslevels 
and Nemesis 2 has no downdouble. Besides, with most stuff you can't shoot directly with your laser, you can do the option trix0r. You place your options beneath you, and just wait until the options go through al kinds of background collision thingies and start firing whenever they get out of it to shoot the otherwise unreachable targets ^_^
that's how you should clear the huge endboss ship with the little cannons inside in Nemesis 3, forget tail beam!! just make sure you have shadow-options enough speed, and any kind of laser (i prefer screwlaser) place your options as far to the front as possible, and let that big mother$#%# scroll into them... happy firing ^___^
I always felt the best weapon was the little grabber-arm from starship rendezvous 
Doh... Hentai 
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