Here's another strategy, I beat this round on my first try before I found out that it was supposed to be really hard. My secret: The Reflect Spell.
Okay, People, reflect is a lot different than the Aero spell. Unlike that one that stays with you, Reflect is only active for a couple of seconds. Bad huh? WRONG!!! During those precious seconds, if you get hit, you will not take any damage. Also there is a second function. Once you get hit, the spell will explode, damaging your enemies depending on the power of the attack. And don't forget magic combos, continue spamming the spell to the finisher, and the damage will be a lot more. Also do not forget about reaction commands, those can help in a pinch (Heal stomp persay). Unfortunately you will need to glide around a lot to recharge, but overall this round was easier than that time limit one (I hate time limits). I did this without any potions and without trinity limit, so it can be done. It was tricky, but I did it.