Yeah, those essences got nerfed into oblivion. They used to be able to exceed the level cap letting you do completely wacky bullshit like level 1000 characters, but now they kinda suck. I really wish they had left them alone, to be honest.Devil Growth:
Hm, I can use it on a Max-Level 5 Character, but not on a Max-Level 10 Character (play with "Free Play" and current max-level is still level 10) so this seems kind of useless since I can just fuse a level 5 character with a level 10 spirit (light-spirits level ultra fast) and not tank max Morale ...
Lightning Storm:
Meteor Storm is nice and I get it very easy just from Fire Plant and Fire Beast (Plant and Beast + Fire Hyprids) which have Meteor. So just fusing 2 of them gives you Meteor Storm (The plants ALWAYS have Meteor, the Beasts have a 50% chance but with Evolution I can just change the skill set). But If I have to fight "fire" enemies Meteor Storm is obviously very weak and I want other stuff like, Tsunami and Lightning storm on my team. And Tsunamis you just get from the water spirit evolutions directly. Lightning storm is especially nice when fighting water enemies (that take very little damage when in Water from fire (like Meteor Storm) and Tsunami but take DOUBLE damage from lighning attacks ...
As for fusing, there's other benefits to longer fusing chains, and I'm trying to avoid completely giving it away unless you ask lol
Lets just say that skills are not the only thing you're concerned with while fusing that many spirits together.