Thanks to watching your video I smacked her in this quest. I had been dodging the fire blasts and backflips, for some reason it never even occurred to me to Iai slash through them, ope. I had a 7.5 thunder longsword and 3 thunder attack so I beat it a bit easier and quicker; I'm hoping Rathalos wont prove much of a challenge with the same setup. If you have a video of that I might give it a watch for inspiration!