Its not uncommon for power systems to include various creaturee through its logics & mechanics as a source of conflict to give characters to fight. Theres been many different interpretations too, such as curses from JJK that are manifested from negative emotions. Im just wondering how other series approach this idea
There are many magic systems that have complex layers of mechanics and logic that sustain it, but I think its really interesting when you need a certain mindset to truly master magic. A good example is ATLA, where benders use martial arts to move & think like the elements while drawing inspiration from how theyre all interconnected. Every style reflects a different philosophy to manipulate the forces of nature, embodied by ancestral/cultural heritage that grants spirtual power. Another one is JJK that rewards recklessness, sacrifice and taking risks when you must trust your instincts.
Personally in my magic system, all abilities are driven by a sense of vengeance and unleashing consequences onto the world that reflect ones will & rewriting fate