Mc will live underground, he would have started in what he thought was a form of skyblock: just a single tree, 1 dirt block, surrounded by stone in all directions and acess to lots of mods. Only after mc completes all of his mods he decides to go crazy with building stuff, he makes an entire city underground just for him himself. Mc noticed early on that one of his mods gave him a block that simulated a view to the sky(so he can have beacons and etc while still underground), so he never bothered digging up, but one day when he decided to build a replica of the empire state building, mc actualy ends up hitting a sewer tunel, uppon investigation, he discovers he was under fuyuki city the entire time
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Mc will be endgame skyfactory by the start of the story, [draconic evolution] armor and weapons, mix of [matter overload] cyborg and thaumic horizons body modifications, etc etc. Mc will save sakura at the start and go [thaumic horizons] on her body to help heal her soul(sure, she does not have the best experience with body modifications, but mc promissed he can make her a normal body after she finishes healing if she wants(she will instead ask for the full package mc is using instead when the time comes)), sakura would be maybe 8 or 9 years old by then(no r*pe! Poor girl suffered enought in canon before fate stay night author decided to twist the blade even further with that!) and she then becomes mc's aprendice in the many magic systems he know about