When usingsince the game is in beta test why not cheat. use save edit online to edit the amount of shield juice, so you will be unbeatable on this silly fight mechanism.
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on a savegame:Item#73 (Page of Knowledge)
Variables
Variable#2 (money)
Those helped me a lot. You can only get one shield juice, of course if you find the 1, you could make it 99999 probably.
I could find out more, but saveeditonline starts complaining after a few times.