The idea for this series, and therefore Jack's character initially rose from one of those perennial arguments you see online. In this case, it was an anime thread, and the argument was whether subs or dubs were the proper way to watch, and how much of a subhuman goober those halfwits who watched whichever you didn't were.

Jack's initial thought regarding the language; "I watch anime, and read books," was one of my standard responses to that. I've only ever followed two subbed anime, and only because I can download them. That way, I can stop, rewind, and catch the subs. Otherwise I spend all my time reading the bottom of the screen, and none of it watching what's actually going on.

The thought came to me, what would happen if a character got sent to one of these worlds and didn't speak the language, because he'd insisted on watching dubs? How would he cope?

Then the question became; how would he have gotten there? Certainly those sending him, gods or whatever, wouldn't do anything so dumb. So, he became somebody who'd been sent to the wrong world. Chapter 1 explains that.

Initially, Jack was your standard isekai'd anime MC, just American rather than Japanese. Given his nationality, he'd differ from the run of the mill isekai MCs in both culture and skillsets.

So, he became a veteran. None of the dark stuff yet, just a veteran with some military skills. He was, however, always going to have sword and archery skills, much as was written in the finished product. All of that was in the initial outline.

The PTSD, his history of medical issues, the meds required to keep things together, that all came later, from my interactions with several Iraq and Afghanistan vets I've known over the years, and how their time and/or injuries sustained over there affected them. TBI is apparently a very common reason for discharge in the modern era.

And the chronic back, joint, and bone issues that the VA insists aren't service related are stories I've heard from guys who've been dealing with them were eventually added as well.

This story originates from a different website. Ensure the author gets the support they deserve by reading it there.

His skills grew from my experiences with HEMA and SCA, and the great strides those disciplines have made in the past twenty or thirty years. In the '90s, nobody'd ever heard of HEMA. It was all about Katana. SCA was a thing, but the two are only superficially similar. SCA fencing was an interesting offshoot, and much more practical than Olympic strip fencing.

Here's one that's probably going to be a surprise. The staff was never supposed to be his primary weapon. The jaeger drop sword was meant to be his primary, or a bow. Further, the staff was supposed to just be a staff. All of the odd/extraordinary things that came about with FoeSmite turned out, in the end, just as Mohrdrand predicted. Nobody knew what the staff would become until it became. More on that later.

He wasn't originally supposed to use magic. At least, no more so than any Mundian adventurer. His Artificer class was supposed to have evolved from his Earth experiences as a student machinist pre isekai. As his sentinel class grew and developed depth, though, it made sense to allow him certain extraordinary powers.

In part, the drawbacks of the sentinel class grew out of my total inability to play evil aligned characters in video games. I've tried, over and over, but I just can't do it. It's cost me many an achievement, let me tell you. The weight Jack feels to protect and rescue grows out of that. I'd often find myself roleplaying, and haring off to rescue some random NPC, just like Jack hares off to help the mice.

I even figured out how to rescue the guy who's supposed to get murdered as you enter Markarth in Skyrim. It requires a dragon shout, but it can be done. I'm kind of that way in real life, too, although I don't suffer from Grim Resolve the way Jack does. Well, not much, at least. It's gotten me in trouble once or twice, although I've never tortured anybody.

Initially, he went into the bandit camp alone, and there were fewer bandits, and no dark mage. That was retconned rather late in the process. Within the past couple of months. I like the current version better. YMMV.

He was also never supposed to end up with the magical girl. I had a whole other path set up for him. As I said in the Rosaluna extra, Tiarraluna was supposed to guide him to town and go back to her grandmother. He was originally supposed to have a minor harem in the vein of the more common isekais, although without the obliviousness of the common Japanese isekai MC. He may still have going forward, but his reasons will be different. We'll see how things work out. My characters don't always follow orders.

Anyway, there's, broadly, the changes he went through from my initial outline to finished manuscript.