I didn't get the sense that there was any chance to use actual tactics or strategies. It's just constant enemies doing mysteriously hitting attacks directly at the player character. In particular, the 2 areas felt more like a frustrating contrivance rather than an interesting mechanic. I think you need to slow things down and think about what the player is actually supposed to be doing, then try to convey that better or make it more feasible.
I'll say, there's actually small but a good number of strategies you can do here! Specially at some boss fights! For example: Take advantage of Thunder Rain since it paralyzes enemies and you can use and charge your weapon! Light Barrier, Defence Potions and Invisible Potions will help to avoid most damage! Offense Potion will make some battles even faster! Unfortunately this game is still clunky and not on a finishing ground (as the battle system I've based is INDEED complex at first sight), but I'm still trying to tune it down and making it not too simple but not too complicated! A lot of balancing stuff that I've wanted to implement wasn't brought in time, but it's still playable at the limit. So yea, there's no much I can do right now until the jam end.