Magic in world-building can be complicated, but fun to write/draw once you have the mechanics and rule sets down. I built the whole world of my web comic using Pathfinder & DnD abilities and spells for each character, along with their character sheets to track stats, skills and ironically, hit points. Its important to have rules and limitations that spell casters and the magical world in general, otherwise you just have God-Level characters running around doing whatever and destroying everything.
The magic system in my webcomic, 'Realms of the Fallen', magic exists within each character as spirit energy and latent in the world around them. In Episode '1-24: Magic Channeling 101' , King Ciero explains magic channeling



Magic casting can also be utilized through pre-written seal runes, these are magic rune tattoos that King Ciero uses for instant casting without focusing the spell. Each magical runic tattoo has a different function and spell from Pathfinder/D&D rule sets and all spells / attacks have power levels based on each character's stat sheets I made.

Here's a character sheet back down of Ciero's magic runic tattoos, the language on the Post-It is 'Avian', the magical language of the world.

As for magical limitations, there are some rules that are set for the world:
Society Rule: Blood and Dark Magic are illegal (i.e. possession, ritual sacrifices, Mage Hand's ViceGrip, any magic used to hurt or kill is a crime)
Comic Rule: Instant Teleportation without the use of a Portal Waypoint are limited to 4 characters (1 goddess, 1 demon, and 2 main characters much later on in the story)
Comic Rule: Chronomancy (Time Manipulation Magic) are limited to 2 characters (1 goddess, 1 main character through the help of a 'focus item')
Comic Rule: 4th Wall Manipulation is limited to the Goddess character, while the Demon is aware is something beyond it.
Its incredibly important to set magic ground rules, especially when dealing with God-Level and mortals characters on the same battlefield, otherwise you get 'Thanos Snap' level of inconsistencies, specifically when 'Time Magic' and '4th Wall Manipulation' can just retcon the whole thing.