@Ladyrowaan You’re not alone in lamenting the challenge of the Class Trials, as this fairly lengthy thread shows:
(@Kerridoc @Rook @Coppersky Possible Merge of Topic)
Meanwhile, there’s a new post from earlier today with someone arguing they should be harder. (At least the first two stages.) So I guess suffice it to say the experience with them varies a lot across players, it seems.
Personally, I’ve found the first stages easy, and the last stages doable but somewhat challenging. But I have a decent roster of 4* heroes at this point, along with plenty of leveled 3* to fill in where needed, and a couple 5* heroes I’ve started working on.
They definitely require having a wide breadth of leveled heroes and/or some strong battle items.