This mission, along with M10, has a different requirement for Master Rank. For these two, you can miss an enemy, because the kill all enemies objective was replaced with a time objective. You still can't get hit, so it doesn't really change much. In this one, you also CAN'T get hit with EMP. For the boss, I recommend that you always destroy the hit point on the left first. Also, the turbo controller helps a lot with destroying the hit points quickly. You can take it slow; the time objective seems pretty lenient, shoot in small bursts, and only reload after you destroy the EMPs.
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