@BronzeAgeBrain Daggers Twirl is a block, Knuckles Sway is a dodge And Whirlwind parry is.. self-explanatory. Additionally, as fighter, your Overload will fully heal you once it expires. Ideally, just go Fi/hu max out Ironwill and Stalwart Spirit, Guard stance, absorption, and Healing Guard (works with Double saber weapon action) put a 2 points into fighter Overload (so the status affect only lasts 15 seconds (Stalwart Spirit lasts 15 seconds at cap, so you'd be ostensibly invulnerable during) Critical Strike, Adrenaline, and cap out Slayer, beat and heart skills, and you will be able to heal against her. Take an ice weapon that specializes in single target attacks.
For Techter, go Te/hu take Nabarta Type 0 (heals through absorption and Healing Guard), and just proceed to dash'n Smash with an ice weapon with Reactor and wand lovers on.
Did it with Fighter. Took more Iron will rolls than I’m proud of after switching out of knuckles and into TD, but I beat her all the same. The build you are suggesting is probably a bit extreme for one optional quest. I was specifically talking about counter damage. Fighter has plenty of I-frame and guard-frame attacks to get through. You still need to play really well, but it’s more than possible.
Techter is no lie probably easier to do with Te/Fi than Te/Hu given similar affixes. Just pretend your a poor mans Fo/Te and it’s S rankable. Otherwise from experience Te/Hu doesn’t have the damage. Just Ice element and Nabarta-0 doesn’t get you to phase 2 with enough time to complete, even with a Nemesis wand. You need to be juggling at least Ramegid-0 at the same time, and/or getting sneaky Zanverse casts out. That requires managing Ramegid-0, barta for when you need to reset wand lovers, and dealing with Phaleg at the same time. Oooooor you grab a talis with your rod and Ilbarta through the first phase with Te/Fi and then Ilgrants/wand smack through the second.