Perseus Black: The Origins of the Grey Lord

Duelling

AN: The idea of measuring magic I got from the fanfic Harry Potter: The Artificer, or something like that I can't really remember the name. However it is a really good fanfic and I recommend that you give it a read. Although this is a crossover, I'll be taking inspiration from numerous books, both original books and fan fictions and I'll try and tell you where the ideas come from. I don't own Harry Potter or Percy Jackson, that is JK Rowling and Rick Riordan... I think  

Currently Percy was in the library researching about how to power runes using magic, and about magic replenishment. 

It came to him when he got given a letter from Tonks, that was written by her mother, and his aunt. Apparently while Andromeda was beyond angry that somebody was trying to get in the way of her and her "baby sisters baby" from getting to know one another, she was rather glad that he hadn't received her letters and wasn't just ignoring her for spite. She also said that she didn't really mean when she said that she had mixed feelings and was trying to guilt trip him and would love to meet with him. 

She did decline about going to the Yule part hosted by the Malfoys, purely because she knew that she would be shunned and Ted would find it uncomfortable, however she did ask if he would be willing to spend the day with her and her family at some point during the Yule holidays.

After he agreed, the floodgates of letters opened and he soon started to reference her Aunty Andi, something she insisted he called her, a nickname his mother gave her. 

Anyway, Aunty Andi would talk about how when they were younger, his mother, herself and Bellatrix would often duel to determine who was the most powerful. Narcissa wasn't as bothered as the other three and was more focused on politics than anything else.

 Soon it was obvious that Aquila was often the most diverse in her magic, using Charms, Transfiguration, and proper duelling spells to win her matches, however the power in her spells was the weakest out of the three. 

Andromeda herself was the more precise in her spell work and the fastest, according to the woman it was near impossible to dodge her spells. 

While Bellatrix spells packed the bigger punches, and relied on brute force to win the mock fights the three sisters had. It was also her tactic when she entered illegal duelling tournaments, one's that often resulted in death (in actual fact Percy already knew this, his Aunty was always telling him stories like this when he went to visit her in Azkaban, a right he only had because he was her heir, it was in these duelling circles where she would meet Carlson Mulciber for the first time, a man who was widely recognised as Voldemort's first right hand man, he met his match in an up and coming auror by the name of Alistair Moody).

A young Aquila Black would often claim that there was no way to check how powerful a witch or wizard was, as if they were able to, then they could develop a plan to increase their rate of growth. 

This is where Percy's idea came from, and why he was currently in the library. If Percy wanted to become powerful, and if he could put a number on how powerful he was, then he would be able to see how much he increased by.

And he felt Runes would be the way to go.

The theory of Runes is that they are powered by a persons magic, the more powerful the magic, the more powerful the Runes and the longer they lasted, well that was the idea.

If Percy could figure out a way to create a Rune to measure how much of his magic he put inside of it, then he could give a rough estimate on how powerful he was. He already spoken to Professor Babbling about this and she was impressed, she pointed him to some books- books he was currently studying now- and mentioned that he should speak to Professor Flitwick about magical cores, an area of expertise that the half-goblin had some expertise in as it was the subject of his Mastery in Magical Philosophy.