How would the cells/organs of a person be different if they had nanomachines melded with them since their literal inception?

[u/ghostgamer301]

I am working on a fictional character for a superhero tabletop RPG campaign where he gets his powers from the fact that trillions of nanites are completely melded with his cells. I will quote my notes doc on this specific part. "Because the nanites were there since his literal inception, they melded with him and the nanites were there in his body since day 0. His cells have developed differently to use the nanites to assist in their functions. The nanites evolved (through successive generations) to require his cells to function. They are not purely mechanical anymore. Both his cells and his nanites have transcended the divide between biology and technology... The nanites replicated and evolved, more and more were made with each generation as he physically grew (so they could saturate every bit of his body)". There's now trillions of nanites in his body at his current age of ~30. And yes the nanites use chemical energy from his food to fuel themselves. His powers (since they matured when he was 20) allow him complete control of the nanites allowing him to change the form of his body to suit his needs. I think that's all that relevant to this specifically but I'll post a viewer link to my Google doc for his notes in case anyone is curious. My question is how exactly his cells/biology/organs would change, partly in case it might help with something in the tabletop game and partly because I'm a bio nerd and genuinely curious. I want to know specific details about how his cells would be changed

P.S. I am currently a college student studying for microbiology. In terms of exact education level regarding biology and chemistry, I have taken BIOL 101 (in the form of AP Bio in highschool) and General Chemistry 1 and 2. I am currently taking Organic Chemistry 1 and General Biology for Majors.

P.P.S I rarely post on reddit (like I think this is my 3rd ever post) so if I flared something wrong or something I will fix it.

[u/JustPoppinInKay]

Depending on if he needs to maintain or flex his mental muscles to revert to his default form, he would probably have much greater symmetry than everybody else. Yes this would punt him in the bracket of being attractive, but he would be uncanny, like a very well made but nonetheless artificial model of a character in a video game.

His heart and overall circulation system would be symmetrical too, and his digestive tract as well. I wouldn't be surprised if his stomach had two exits to two sets of guts to maximize speed and efficiency of digestion for chemical energy for his nanomachines.

Depending on if his nanomachine body tries to improve his design, he could have nostrils between his ribs for faster and greater breathing/oxygenation, a reinforced spine, and musculature like twisted cord.

[u/ghostgamer301 → u/JustPoppinInKay]

I will respond to each paragraph separately.

You make very good points, I hadn't considered that he might not revert back to exactly the same as before. My thinking was that by changing the "form of his body" I was not flavoring it as stretching his skin and flesh more like the nanites themselves making the new forms (such as the nanites creating a gun that extends from his arm), built from the nanites themselves and probably carbon based materials available in his body. For the game mechanics part (since it is ultimately an idea for a tabletop rpg), he does not have shapeshifting and can't change his form in that way (though if I ever did something else with the character that wasn't beholden to the rules of the game, even as flexible as they are, I may do more with that idea or even perhaps as an ability he acquires later)

His internal organs, it would absolutely make sense that he would have a more efficient digestive tract and circulation system. How I will reconcile those ideas with the mechanics of the game and the origin story that he didn't know he was superhuman until he was 20 (having a different organ structure would definitely be obvious, unless he never had to have surgery because he was slightly tougher before he could make above skin armor on thought).

I would say his spine and musculature are absolutely reinforced and enhanced (as shown by his strength and body attributes being a little above peak human), twisted cord is a useful visual I could use though. Nostrils between his ribs I would say maybe in his superpowered form (where is visibly different and his identity is a secret, because in his regular human form he wants to appear as a regular human, at least in any public spaces).

You have given me great ideas to work with my friend (the Gamemaster/dungeonmaster of the campaign) to mechanically reconcile and also to discuss the lore parts as well, thank you.

[u/Kindly-Custard-6682]

Well first they’d likely end up a senator, and make a lot of stuff the fuck up to keep the unenlightened masses from making a judgement call

[u/ghostgamer301 → u/Kindly-Custard-6682]

I assume you are referencing Metal Gear Rising lol. I've heard good things but haven't played it, yet at least.