I like how in the Guardians of the Flame series one of the college studant AD&D players who is sent by their Professor/DM into an alternate universe as a magic-user decides to forsake magic and use his intelligence for something more constructive that benefits his new world and everyone in it.
Each of them have kind of split personalities since their arrival to this fantasy realm but with a strong enough will one could choose to ignore the new personality and allow the old earthly one to dominate. They pretty much all end up doing that but not to the extent that Lou does.
He was studying engineering in college and so he begins applying his knowledge in this new fantasy realm which has never before seen gun-powder, fire-arms, and all sorts of public construction projects he initiates.
Lou forms a guild for his craft and trains others. He becomes one of the most powerful forces for law and order in the land! [They didn't call em 'peace-makers' in the Ol'West for nothin you know...
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