A possible side story to Power Windows?

What would you guys think if I did a side story within the Power Windows universe?

It would probably be a pony getting put in Socobeck and being forced to survive along side another main character from said world. It would be a great chance for some major world building and just something fun to do for me.

I've also been toying with an idea of a group of people who gave their souls to gain the power over life and death itself, at the sacrifice of imbuing a specially runed weapon with their own soul to gain that power and to make the weapon a "soul weapon". Their abilities being inspired by the Death Knights from WoW and from Shadow of Mordor.

These people would be split into two groups, ones concerned with ending life, and ones concerned with preserving it. I'm thinking that they have a dislike for each other but are bound by a mutual agreement to keep things in the balance. How one joins this order is either by death and them seeing use for you, by being cursed to serve by one of them as a form of punishment, or by happening upon a lost soul blade.

There are three different classes to these undead knights, Soul Renders, Blood Knights, and Necromancers.

Soul Renders specialize in souls and spirits, think of them as the sort of "mage" or "caster" class. They can drain the souls of mortals and commune with the spirits of the dead to be their weapon. Whether it be possession or a good jump scare, soul renders have you covered.

Necromancers specialize in disease, decay, and raising the dead. Now you may be thinking "Isn't that a second caster class?" surprisingly no, Necromancers are more of a rogue or footman type of class with all of their diseases needing to be applied through touch. They often let their minions do the fighting for them, with them picking people off in the battle. Or by causing chaos by giving someone a disease and having it spread around, completely in their control.

Lastly we have Blood Knights, the tanks. Out of the three these guys are the closest to being alive, still having a fully working body and mind at the cost of a soul and their emotions. They can control the life essence of a person, whether it be their blood, or their organs, and have the ability to steal someone's life force to give them power. Because of their abilities over blood, they come packed with super strength and Wolverine-like regeneration (not immediate because that would be OP, getting a limb cut off would still put them out of the fight but not permanently.) This class is also the most difficult to become, as well as the most dangerous to be. Because stealing someone's life force is so addicting and power-giving, it can be pretty easy for a blood knight to become tempted and go rogue from their order.

Now you may ask "How do you kill that which cannot be killed"? I have your answer, "Control the sword, control the knight." Break the soul weapon and the soul is destroyed, thus killing the knight. If you were to obtain this weapon they become basically your slave, a knight is powerless without their weapon for that is their source of power in the first place.

These knights, are known as the Desh'noka. Though the name is subject to change, i'm not sure yet.

Now the main character of the story would be a Blood Knight, and his name is Goriball. That's all I have for details on that.

Let me know what you guys think because this sounds like something that could be really fun to write.