Yeah I've found myself using most of my 3* for skill ups, since almost every type has at least one element that's good. Exceptions are like, Salamander and Golem...It would take less experience to level the threes, but the twos are worth less overall and are easier to part with.
Ugh, fusion hex. I keep thinking about this, but I can't imagine doing it, at least not for a LONG time. You have to take each, evolve it at least once, and awaken it, before you can fuse it. I assume that whatever comes out is level 1 and unevolved? No idea on this, but it is my assumption. I am not sure I would want to take a 4* awakened fire magic archer, for example, to get a level 1 unawakened fire joker. Then you have to 5* and awaken the joker, fox and ninja (plus a martial cat) to get the phoenix. Then I assume you would have to awaken the phoenix still. That's LOT LOT LOT LOT LOT of high essence farming.Worst Phoenix is better than no Phoenix!
I've found that Wind Imp/Water Hellhound do a pretty good job of blasting through the shield unless they have fully HP runed her. I just avoid those fights if I look and see she that she has 7k+ HP.Monster discussion time:
Wind serpent may be a great way to blow up Rina (water epikon). It's main attack removes buff 50% AND 30% chance to hit multiple times, ala inugami. Also has passive that reduces fire dmg by 50%. Pretty great if runed with speed and accuracy perhaps