About "Blake Gripphin battle in hard mode

right now i'm battling elder gripphin and you know what
i try all i can try just like for an example gravitron's laser,tame,3 hits and omega boost but it remains in vain and i think i dealt 20000+to elder griphin and it still wont die!
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i try all i can try just like for an example gravitron's laser,tame,3 hits and omega boost but it remains in vain and i think i dealt 20000+to elder griphin and it still wont die!