Blu Mage fight 31 not enough dmg

[Clawhammer]

Hello!

today i did the blue mage arena 31 and finished the last mission. However after all this pain i decided to suffer more and wanted to do the "Violets Are Violet" Achievement to get the title "Of the Truest Blue".

As far as i understood i need to do:

- The whole 2 stage fight in less then 6:50
- No dmg from the aoe attacks

I did the first successfull run with aetherial mimicry in healer mode and yeah it took 15mins to do the story and play safe, so iam now into full attack mimi mode.

But omg, i need +5min just for the first stage

After that, i watched this video:

https://www.youtube.com/watch?v=CB6EHXud-GI

And this guy is throwing 10-12k dmg with his attacks while my mustard bomb for example only hits with 3k.

What iam doing wrong?

I spam no 78, 48 on cooldown, i keep no. 20 up all the time possible and my main attacks are mustard bomb or sonic boom.

How can i deal much much more dmg to beat this in 6:50? Thanks for help!