1) I know you didn't mean it so I'll point out that as written Discounts "100 cp is free, everything else is 1/2 off." means that ALL 100 cp things are free and EVERYTHING else is half off.
2) Here's a build, going with the normal Jumpchain logic of origins providing discounts.
Secondhand Smoke (+100) >It was already a problem back then if I recall.
War Of Women And Children (+100) >So, I'm twelve... great
What You Start With (+100) >One's own reserves can't be expanded but can one tap into the reserves of others. Questions for later.
War Is Hell, Welcome To Hell (+100) >I know how this goes.
I Came Here To Mock You (+200) >Better to burn with humiliation than to burn with actual fire I always say.
It's Not Mandatory (+200) >It is now. I'm going to lean on that nice Buddha guy and have my stuff come from invoking Jump-Chan as my lady savior.
Anti Beauty Failure (+200) >What's a shota? Why is this weird Japanese chick here again?
You Must Undergo Hardship (+300) >This is my second build, right after https://pastebin.com/tEZF6SBw
Origins: Scientist + Mage >I agree with >>58485144
it's a solid combo. You have the ability to do your own research, if nothing else.
Location: Akitsukushima >Huh, so China/Japan if they went the way of England?
An Education (Free) >Going to with a perfect knowledge of Magical Technology Engineering since I don't have any bases for it otherwise
Eccentric Genius (-100) >I am a twelve year old genius Magi-Tech Scientist Wizard I NEED this!
Computation Creator (-200) >THE NUMBERS MASON! I KNOW WHAT THEY MEAN!
Deus Vult (-300) >I dunno if we'll take Jerusalem with my work, but you could give it hell of a go
Fine Control (Free) >Work smarter not harder. We shouldn't look towards growing ever stronger, but in maximizing control over what supply is considered average
War In Three Dimensions (-100) >This is something that I likely won't ever use Oh I doubt that