What are some of the best PAs to have equipped for boss fights and big damage?
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You don't use launchers for bosses unless you're able to hit two bosses at once with Cosmo Breaker.
For rifle you use Satellite Aim or Positron Blast depending on the fight. You can use Impact Slider during movement phases to keep dps going while giving yourself iframes.
Photonic laser on launcher is good for anga when the boss swaps to rifle resist or you can hit a bunch of mobs like on falz elder hands. As stated above though the rifle is the weapon for bossing. Launcher is for regular mobs and most other situations. Satellite aim is a gunner pa, satellite cannon is what they are talking about.