Hey, I don't know if anyone has said this before but...
I have a theory that exp, is actually quintessence. It seems logical, to me at least, that when you kill someone in Fire Emblem, you get their quintessence.
How else do you explain someone training and training devoting themselves to their skills for years, and they're still level 3.
But as soon as they start killing people... Boom! Level 12 in 4-6 levels.
I know there are going to be inconsistencies when we start getting into this. (Full disclaimer, I have not beat the game yet, I'm going off of what I know so far (Ch26 Battle Before Dawn))
But kinda what I was thinking was, that when you kill someone you get thier quintessence, but it takes that special magic to harness that quintessence into a storeable form, so that you can then give it to SOMEONE (Nergal), or use it for certain rituals (Like summoning dragons).
I thought of this Theory during one of Marth and Kris' supports (FE12). When Kris was talking about the rush got when he "Basks in his newfound power" after defeating an enemy.
Thank you for reading my weird theory, I hope you enjoyed on some level ^^
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Just finished chapter 26, and did a little research, we see quintessence taken from people alive and dead, so if it just is residual someone might be able to absorb part of it? It is a very mysterious substance this far in the game.
Again dark magic is there to take ALL the leftover quintessence, or all of it if the person is still alive.
I think that through discussion this is making more sense, to me at least.