i found this walkthrough helpful, http://epicwarsaga.wikia.com/wiki/Beginner’s_Guide
first time playing the game, and this made each level painless, im on 4-4 right now.
side note (i mastered each level before moving on, except maybe first boss, but went back to it soon after. cant really remeber)
i didnt follow it presicely to a T, one thing i did was have the exp rings equiped along with 1 exalibourne, and 3 holy staffs. and when it came to fight barbetos, i swapped rings for 2 zues staffs, but after mastering i put them back, u may not even need the zues staffs
and one more thing, u DONT need waste crystals for holy mantriach like the guide says, just spam succubi and stay infront of them
and when i fought the first oni, i used valkeries. i dont know what stats to aim for. anything else.. idk