I first had the idea one year ago. At the time I was brainstorming to find a way to bring a Noble Phantasm from the Nasuverse here but I kept going on blanks since I don't want Alaya anywhere near this Universe. When Jeanne asked me what was I brooding for, I told her that I wanted to bring a powerful item for her but had no idea how to do it.
It was then that she said the words that would lead me to countless sleepless nights.
"If you can't bring it, why not create one yourself? From the way you are talking you already know what this thing does."
I was going to call her naive for thinking I could create a perfect Noble Phantasm. However, I started thinking and concluded that I didn't need to make a perfect copy. Look at Emiya Shirou, none of his projections are on the same level as the originals but all of them are still ridiculous powerful.
It was with the mindset that I took Jeanne's banner and went to work, just to get on my first problem. The metal that made the banner was good enough for this period but not even close enough to withstand the powerful magic a planned to input on it. The banner would either break on its first activation or the magic would be weak since iron is not the best conduit for magic.
So, I need to change the material and the fastest way would be Alchemy. My only problem was that I knew almost nothing of Alchemy since neither of my past lives delved into it. However, I had the biggest cheat code ever, namely the Sacred Palace and its huge collection of books. So I went to the Spirit World and for the next three months, all I did day and night was practice Alchemy while chatting with the Djinns'.
Once I felt confident enough to not mess it up, I gathered the material I need from the Palace's Vault, which I found out about in those three months, and changed the banners metal to Mythril.
The next problem was that of converting Jeanne's Magic Resistance into barrier magic which came with the obstacle of me not knowing how Magic Resistance worked on this world. I knew that any type of magic throw at her will deviate from its course never hitting her, as seen in the numerous spars with her, but I had no idea why that happened.
Five months. That's the time I spent on the problem when I finally found the answer. Magic loved her. That was it. For whatever reason, the natural mana in the air interferes with any spells used against Jeanne with the intention of harm. That naturally leads to an interesting question, is Magic sentient? But that is for another time.
Last three months I spent carving runes on the banner's shaft and creating the magical formula to convert Magical Resistance into a barrier against all physical and magical attacks. Today is the day I finished my work, not all left to do is test it.
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"Jeanne, wake up..."
I think it's a little past 6 a.m. and I want to see if my work, well, works. While I think it's blasphemy to wake up the angel sleeping on my bed, I will deal with the consequences later.
"Morning, Damon. What happened?"
"I finished, Jeanne. I finished your banner, let's go, I want to see if it works."
"Really?! I knew you could do it!" She says with a huge smile threatening to split her face. I have to turn my face away from her less I'm blinded by her light.
Once Jeanne is out of bed and changed, we first eat breakfast in the living room before teleporting to the middle of the ocean. Why? Because I know nothing will disturb us here.
"Now, you remember how to activate, right?"
"Yes, I do, relax. I was the who choose the incantation, remember?"
Really, her exasperated face is just too cute. It should be illegal.
"Yes, ma'am. Now, the first test will be again a single A rank spell and I want to if it can withstand. Ready?"
"Yes, let's do it!"
As I gather mana and my silver magic circle appears, lightning race through my body as I start to chant.
"Baal, I ask of thee to empower my strike: Bararaq Saiqa!"
For a split second, the air atomized and in the next a lightning bolt with the thickness of a car raced to Jeanne.
"Luminosité Eternelle: God is Here With Me!"
I heard over the sound of thunder. The second the voice finished an explosion of light happened not letting me see what is going on. When the light show ended, hundreds of meters away from me stood Jeanne surrounded by a golden force field that didn't have a single crack. If not for the slight out of breath state she was I would never think anything happened at all.
"Yes! It worked!"
I laughed and felt, for the first time, truly proud of myself. Before this, I was just relearning things that my previous lives left for me. However, this was all me. This is proof of my hard work. Perhaps, I will live up to the name of Solomon and the title of Wise King.
"Congratulations, love. I knew you could do it!"
A beaming Jeanne says next to me and I couldn't help myself when I kissed her.
"Thank you, it means a lot to me."
Before doing any more tests, we just relaxed for an hour, waiting for Jeanne mana reserves to be filled again. We tested once again, this time under a barrage of B rank spells. The Noble Phantasm could stay at full power for a minute under such heavy fire but past that Jeanne gets exhausted and it loses potency.
All in all, I would say that it was perfect and Jeanne certainly agreed with me.