>>536868412
Well, that might be a bad example because it's such an easy stage to clear, but NP5 fully maxed and granded Olga clears that easily whether you refund or not. You can completely waste hero creation just to get no refund from wave 2 and still crit for over 600k damage total + extra attack if Murasaki survived.
The previous setup with the friend point CE also clears also clears if you buster brave chain wave 2 after NP because Murasaki has so little HP. Don't even need to use Koyan's anti-attribute damage.