I'm not sure if Ursala counts as Mid but she made a huge difference in my Chimera runs this week replacing Pythion

I think I'm swapping to more trials focused.  Relic mats so important.  Of course as long as you can still maintain the 1 key

My current setup is Ursala, Gwyndolin, Cardiel, Gnut and Lydia (Cardiel is just extra dmg but also a few trials require Inc Crit stuff). Ursala does a lot of good work since I have to turn off Gnut's A2 for Viper so she can still do the dec atk.

Owl is amazing tho, extending debuffs (except Ram) and helps with a lot of trials. I think you can get 15 trials done with that team

HH team optimizer has an option to search for recommend teams for most trials completed. I finally built my sniktraak because of that

Cardiel was on my list to try out.  Has a lot of utility for that fight and in a toxic set can maybe get the poison trial done on Viper.