I get it now, we are operating under different assumptions. You believe that the transformation wouldn't be permanent. MC would just transform a percentage of his energy into some other form, and when he expends it, he will regenerate the original.
I believe that any change to his lifeforce will persist, until he decides to change it back.
My reasoning:
Clue 1:
Unlike most Superhumans, MC has 2 traits. Body and Memory.
When MC rests/eats and recharges his lifeforce, what trait gets replenished?
This idea points to life force not being tied to the trait. MC can use his energy at will, for either trait.
So in order to use another trait, he has to somehow transform the whole mechanism, not just a percentage of the energy.
Clue 2:
The idea that MC's powers may get weaker is iffy.
MC should have the exact same output no matter if he has 200 or 400 Power in the tank. The only thing that changes is how long we will be able to maintain his transformations and regenerate his wounds.
So assume that MC is a 400 Power Superhuman
He transforms 200 life force into a fire breathing power.
He then goes and eats 500 cows and gains back 200 Power.
At this point, is his Body power weaker or not?
If it's weaker, then it's not just a matter of energy. He also weakened the trait.
If it's not weaker, then your idea should be correct.
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These 2 interactions make me think that if MC ever manages to transform himself in a manner that allows him to use other powers, this transformation will persist for as long as MC maintains it.
MC can choose to incorporate it into his default form.
So if he transforms all the impurities into Memory and then incorporate this change into his default form, he will forever become a 50% Body 50% Memory Superhuman.
PS. I'm going to reiterate, for the rest of the readers, that I don't expect this to be important at all. It's just a silly exercise, not a prediction. I don't care much about MC using powers from other traits, nor becoming "pure".
The only way this particular interaction would interest me would be if it allowed MC to ressurect his victims, complete with their powers.
It's a good theory, and your arguments are good too and at first, resurrecting someone is what made me think that mc should be able to use other powers in the first place, even if it would be complicated to handle so much possibilities without killing the interest in other character fight and their evolution as superhuman.
What made me think that he cant change it permanently is mostly connected to the 4th. and also Ella about maintaining something as long as we put power in it. (even it she talk about physical object , if it's realy possible,nothing stop him to create an articial 3rd tank or more that he could maintain with is own pool of energy, but would weaken his other during the time he maintain it)
"But my Mom is one of the few who wants a half and half, who's willing to compromise focus and strength, for versatility and the high connection that comes from it."
a 50-50 with both body and memory is weaker in therm of raw power than someone more oriented on one of them.
In theory mc could use that same abilities that Ella used to protect herself against Malik (if he had enough life force) but shouldn't be able to maintain it as long as Ella can because Malik mention that it cost her a lot of energy, and also shoulnd't be unable to use some more powerfull/costy abilities whitch for me is the main difference between lower % and bigger (like Alice that even impressed mc because of what she could do compared to him at the same level)
A 50-50 would have two 'tank' with half-half amount of an unique life force in each when a pure spawn or monster would have all is life force on one to use more costly and/or destructive abilities (again Alice in comparison to mc is a good exemple to that, she can put more power in her attacks than mc even if they're power should be roughly the same because of that cap before level 3).
Both tank would regenerate at the same speed as one because it's would be the same amount of life force just splited in two in a 50-50 case.
And if it was really possible to change that permantently by increasing it's capacity, it wouldnt be much of a compromise on power, and also Sylla talking about trying to balance everything rather than turning mc into a true 50-50 confort me in that.
It's why converting one into another would be more believable for me if it's temporary dont pose any real problem(and since Xanthe mention it i think that it will come to handy later), because it wouldnt allow mc to go beyond his limit but would still give him an extra pool of energy in the long run.
For mc resurecting abilities part, i still think that he will be able to do it, and probably sooner than we think.
With Charlie who think that Oscar is still saveable, Claudia dream where we can see Sylla alive in mc mariage could be a possible futur + it dont make much doubt that Ella will make her comeback rater sooner than later can lead us to think that people can be resurrected by other means than just Nyx mark and if at first i thinked about mc resurecting someone because of similarty with Nyx and memory and all by himself, the more i think about it and the more i think that it will be a combined effort with Deryl rather than just mc .
They already could do something similar with Laurie but imperfectly, (Deryl recreated the missing parts of Laurie's body and mc used is memory power they could rebuild her body) and now Deryl work to complete is philosopher's stone , " the ability to heal all form of Illness and also give immortality"and mc is focus on is memory side and Sylla will also teach him some thing.
Ella body is dead but intact in HERO base, Deryl could "heal" it and mc taking care of the rest with is memory power (with Ella's doll) so together they could bring her to life (+ the fact that mc could access to the place where Nyx keep the soul's of the people she killed (and Nyx invited him to come again).
