I'm trying to figure out ways to explain the differences in magic and evolution between two continents and their inhabitants rn, since an exploration party had been sent from the main one to explore the other. I figured since the northern continent does not have the world tree and thus not direct access to leylines (roots of that tree) then they'd have different sources of magic and uses of it. Which means people from the main continent won't be able to use their magic the same way.

But the explanation felt incomplete so I added that there's a coral reef in the northern ocean that kinda cuts off the magic from both sides, forcing both continents to evolve differently and develop different types of magic. Kinda like the Wallace line between Indonesia and New Guinea

Generally speaking, yes. There are some places of anomalous power where standard rules of magic don't apply, but they hold for something like 99.9% of the world's surface. Powerful mages will often have their own signature techniques passed down to students, which might result in slight regional variations in how magic is used; but generally speaking mages from anywhere in the world will be doing recognizably similar stuff.

That said, there has been a lot of variation in the rules of magic between historical eras.

Sort of.

The general rule "expend x get y expend 2x get y^2" is pretty consistent. However, the world is very understanding and if you want to follow some traditional magic your family has passed down for generations it will work with you.

Places with different traditions tend to get different abilities. If you've got a bunch of monks who cultivate qi and get to punch super hard while also summoning supernatural energy, that's fine. If you want to do the same with words of power and a mighty staff, fine and good. If you want to go into a fight with power armor, a gravity rifle, and biotic abilities, also acceptance.

If you want to mix and match... There we have an issue. You have to have some internal logic for how the power works. A biotic can't cast spells until he figures out how to use mana, and he can't use the overly long qi based arts until he gets some qi. If he wants to use ATP to become a body horror, that's even harder because you need a specific isopod to use the stuff.

Where you live shapes your powers because of who is around to teach you, what materials are available, and how you see the world. That being said, nothing is stopping you from traveling once you've got a firm foundation. You can learn multiple styles, maybe even pick up sing student who have a better attitude for your methods than the local ones. Because I'll tell you a secret.

Mana, qi, all that stuff, it's all in your head. All the energies are one, you're just trained to see it a certain way.

All magic in my fantasy world is facilitated by the gods. Specifically the humans from Earth Drake Cohen, Stacy Steward, Colette Rose, and Delilah Qian. They are the main characters.

They each define how magic works. Reality is shaped to their whims. To gain access to it you’ll have to legitimately worship them. Which is also defined by their parameters.

For example Drake is the God of Conflict who often values some amount of secrecy and discretion. A true follower knows not to announce their worship publicly except privately. A follower who hosts a public celebration in his name is a heretic.

In exchange you get the magic boons he grants to followers. Specifics vary. You may get some magical encryption or messaging. Or you may get what is basically battle meditation.

Yup. That being said it barely works. Magic is a form of radiation that came with the meteor that destroyed the dinosaurs. It affected the evolution of some creatures which is why mythical creatures are real they just hide from humans. (For various reasons but really it's that at one time or another around the world creatures began to be hunted by humans. So they had to hide ) It's best at breaking the laws of physics and the world as a whole. There are some spells that use runes to bind it into a certain shape and make it do certain things, such as obscure an entire city of sphinxes. But it's hard to control and the backlash is usually deadly. Truth be told, we don't actually know how it works, when it decides to work.

I mean sorta kinda, it's only really around on the searside, but if you bring something with a bunch of magic stuck to it back to the other half of the planet it'll work exactly like it's supposed to until all that magic evaporates.

It's only around on the searside because that's where all the leylines are. Magic boils off of them and bubbles up through the ground where it cools, condenses, and sticks to stuff. But it only sticks to some stuff, not other stuff. The stuff it sticks to tends to get very very dependent on it and doesn't much like the idea of being dragged off to some strange land by a strange person, and that stuff will probably vaporize you if you try.

It’s viewed differently, but works in roughly the same way. Magic itself flows from the sun, the Skyfather, bleeding into the universe from a distant realm called the Sea of Stars, or the Ta’Cori Carda. Once it hits the world, that energy dissipates into the environment and becomes one with the overall lifeforce of the world. This energy can then be harnessed by a select few, the Elect, and directed by their thoughts to create wonders. There are five “flows” to magic that a wizard must use to cast his spells, with each one corresponding to an elemental flow. There is Uar, Earth. Igna, Fire. Balu, Wind. Tyda, Water, and Anim, Life.

Yes the magical laws are the same everywhere on Earth. Although mana conductivity is increased in colder and high elevation regions and lower in hot climates. High mountain mages are more powerful than mages who were trained in the lowlands.

It's cheaper to cast spells in aether dense areas, and you may very well be able to simply fuel magic with the aether in the air instead of needing to supply it yourself. More expensive in the inverse. Other than that it's pretty universal.

I'm still building my world, but no, magic interacts differently depending on the people who wield it or the region where it's found. For example, among humans themselves, a specific kingdom wields a better type of magic than another, just as the rules between them vary. Even if everything comes from the same source, the ways of applying it are different.

My Worldbuilding is still in a pre-alpha build so... (Everything here is not finalized)

Magic in my "world" well not really world in this context, Magic is affected by the dimension of where a magic user is currently.

For example:

Dimension 1: Magic is barely affected, theres no ups and downs on strength and power because this is Earth's home dimension

Dimension: 666: Major Anti-magic power up and easier time casting demonic spells

Dimension 777: Major Normal magic power up and easier time casting angelic spells

Dimension 2137: You cannot use interdimensional-portal-magic to escape the dimension, escape is possible through other means

Dimension -100: All magic types are corrupted, causing all of them to be unpredictable.

Dimension 1831-EX: Good luck.

Most dimensions don't affect magic that much, but a lot of them do have unique properties outside of magic

Same underlying mechanics, but their understanding of it and thus their practices are very different. Those that are within the region that used to be "managed" by the old kingdom use the same approach. But we've already got a few cultures in this same area doing things differently due to being isolated during the old kingdoms golden age.

Plus the typical human interaction with magic is far less formalised and thus tribal communities are using that simple approach rather than the science feel of the old kingdom.

But we only have one "magic" in our world.

The Principles themselves are concrete, yes. How they’re applied and taught per blood will vary based on history, be it claimed or proven.

Though even with that said, the Nalsan blood being incapable of wielding them at all, while Culhan blood is guaranteed to, brings many questions.

The laws of magic are the same in every part of my world, but different environments influence how easy it is to use different types of magic and the prevalence of magical energies. 

For example abundant air magic causes floating islands and easily available airships, while people who live in areas where fire is predominant have learned to harness geothermal energy and can produce a gunpowder equivalent.

There is a continent where darkness-infused clouds constantly shroud the sky so using light magic there is particularly hard since the environment is so devoid of it. This phenomenon was exploited and amplified by the vampires who rule the place.

As an extreme example Limbo lacks physical matter entirely: mortals usually only visit it in dreams but in that non-place physical magic is unusable and mind magic can directly affect the (mostly imagined) environment.

Soul magic isn't very affected by the environment because it's dependant on the user's own nature and possibly the deity they channel.

All this is true only while remaining in the world: people who step into Faerie are beholden to the rule of the Fae, and the void between worlds has no rules at all.

In my world, magic certainly has same rules but expert mages aren't sure about all the rules and the trial and error is quite costly cause they drain your lifespan, your soul. It is possible to cast magic spells without fully comprehending them and the consequences are delayed. The effect of the spell is what mages can't be 100% sure they have control over, but another element is if they want spells be marked into objects: they have to physically engrave them and pray they can hold the energy required for the spell to function.

Yes and no. The core sources are the same but elements are a social construct, so different regions can have different elemental systems.

Magic follows consistent rules throughout my universe, but not all places have equal access to it by default.

For instance, Earth is in an 'age of silence', meaning that it has drifted far enough outside its local leyline that there's little ambient mana flow, and thus very little natural exposure to magic. As a result, very few people on Earth naturally develop even basic magical abilities, and manacite (solidified mana) can only condense in the planet's mantle. Earth fluctuates in and out of its leyline over cycles tens of thousands of years long, giving it ages of magic and ages of silence.

In contrast, Gesarn exists in a near constant age of magic, since the planet's motion keeps it more or less in the center of its local leyline, mostly because that leyline is much larger and consists of many leylines converging. Thus, Gesarn has enough ambient mana to commonly trigger the spontaneous development of magic, and enough natural manacite to power an industrial age based on it as an energy source. But even with Gesarn, there are leylines within the world itself that cause manacite to be more abundant (or easier to manufacture) in some places than others.

Then you have karmic magic. It has its own rules that defy regular 'natural' magic based on mana, and it's only available to a select few (immortals with karmic threads). However, this isn't based on geographic area. Too many spoilers to get into how threads are distributed, but, suffice to say, it isn't random.

Yes, but...

Mortals are scratching at the surface of what magic is and can do like ants on an elephant corpse. So different cultures will scratch at different parts and find different things and ways of doing things. Same underlying principles, very different expressions.

And magic has changed over the millennia. New sources of power have been enabled (via a reality altering artifact), including arcane, primal, and divine. And sources have been destroyed -- both runic magic and true sorcery no longer work like they did. Only fragments remain. Lots of temporal changes. It's one reason that most magic items come from lost civilizations rather than new construction -- the rules for making them have changed with existing ones grandfathered in. They literally can't be made like that any more.

Not it's a bit different as magic changes based on culture and belief. At one place you may have something more akin to wizards and the scholarly folks while in other places you'll have something closer to Avatar with martial arts n whatnot.

A person's magic doesn't change if they travel from one place to another. However, a person may become locked into a particular way of using magic once they learn it depending on the person's own belief, and everyone else's beliefs surrounding it. The rules of using magic and its forms are further strengthened by the people's belief and the people that came before thus it's an infinite cycle that strengthens the rule on how it works and how people may interact with it.

My over arching magic system functions like a frame work. Belief attaches onto the frame and as more people believe, it eventually weaves into its own thing which is why magic systems can vary wildly between cultures and people. There are a total of 2 rules for the frame work. Belief makes reality, which I just described, and secondly is source.

The magic needs to come from somewhere. If the magic has no source within the belief it will take directly from a person's inborn Authority (I can explain in detail in a separate comment but to give a mild idea, I'd liken it to mobalizing the entire US military just to arrest some dude who went 72 on the 70 road. It's waste of resources). If it does have a source however, like say blood, elements, dieties, spirits, mana cores n mana hearts n that whole thing or otherwise, it's far less expensive.

Absolutely not.

Different sources are best for certain types of magic.

Some can be learned.

There isn't one size fits all.

Well, all the magic of the Known World and beyond derives from Mana, swarms of microscopic, eusocial, hive-mind multicellular beings. Humans of the Known World classify Mana into four main classes: Wild, Spiritual, Divine, and Hereditary.

Wild Mana swarms generally require a host, usually animals, to live, changing hosts as soon as the previous one dies. They generally don't affect the host, but in others, the swarm is so aggressive that it modifies the current host in its own way, thus creating Magical Beasts. However, there are some more debatable subtypes, such as swarms that use plants and fungi as hosts, not animals.

Spiritual Mana swarms are free-living, developing mobile colonies, often resembling atmospheric Cnidarians. Popularly called Spirits, these colonies can be "domesticated" by humans called Spiritualists.

The Divine also has a free life, but unlike the Spiritual, these swarms create large structures similar to coral reefs, but terrestrial. They can detach part of themselves and send that part outside the "reef," where this fragment aims to find resources, patrol territory, and attack threats. Like all living beings, these swarms begin small and sensitive, with some being dominated and consumed by animals and people. These individuals gave rise to the Lords and in turn to the Old Gods, Apostles, Agents, and various other types of "divine" individuals.

Finally, the Hereditary are swarms passed down from parent to child, genetically. They are a type of Wild Mana that "took a liking" to a specific host and their family/community. Human swarms produce Aether, a non-Newtonian fluid that can be controlled by humans; elves control electromagnetic fields and have long lives; the Kxinaru control their metallic feathers; the Administrators have absurdly long lives; the Ice People control water through electromagnetic fields; and the ancient Homo metamorpheses could modify their bodies, generating claws, horns, teeth, armor, feathers, etc.

Yes, and no.

Magic in The Moon and Her Handmaids functions at multiple levels. The deepest level isn't even magic at all, strictly speaking, but just the raw information about everything. To quote Terry Pratchett: Nine-tenths of the universe, in fact, is the paperwork. Magic is, on the most fundamental level, editing the paperwork of reality. Granted, it is editing n-dimensional paperwork using tools with far fewer dimensions, so it gets wonky.

The current models for how magicians understand magic are converging on this fact, but it is very difficult to work out exactly how this works, especially as magical investigations suffer from the "you changed the outcome by measuring it!" problem, but on steroids.

Above the paperwork-layer there are n additional interpretation layers which are both abstractions of the lower layers and interpreters of higher layers. It is at these levels where most magicians practice their art. It is also here where things get very weird, and highly variable, very quickly.

There is a very strong feedback loop between the various abstraction layers of reality and the workings of magicians. This is partly what rituals are at a deep level: using familiar structures and behaviors that tell some level of abstraction how to try and edit reality. If one hundred magicians do a ritual in the same place or in similar places, then the local magic/paperwork, will begin to expect that sort of ritual and assume that it is necessary to produce the desired effect.

Since the context of any magic is vast and includes such information as attributes of the magician, attributes of a location, time, the position of the stars, the direction of the wind, etc, all of that needs to be accounted for. Rituals and spells are essentially ways of providing fixed context to things and from that, producing fixed, or semi-fixed results.

However, because of this same context issue, regions of the world can develop their own eccentricities and as such the way magic is performed from place to place can appear quite different. Symbols that mean one thing in Place X mean something wholly different in Place Y. This might mean that using a rose in a spell in Place X likely has the meaning of romance/love etc, while in Place Y it is used to symbolize secrets. A magician who does not know the local meanings of symbols, does not know the right rituals, or whose practice is alien to region might find themselves doing magic they never intended.

This leads to the tradition of "ambassadors" and "alliances" whereby a magician can use their affinity for a particular sort of magic to help transfer their context to a new region. Let us say that Atia the Magician often uses magic involving birds. Birds are her old allies at home. When traveling abroad, she may wish to bring a bird with her and use it as an ambassador to the local birds, telling them that Atia is an ally of their kind back home. This 'updates the local context' to accept that Atia does bird-magic, and that the local magic should adjust to take that into account.

All of this can lead to what looks like utter madness to non-magicians. A traveling magician might think nothing of introducing themselves to the paving stones of a city, or asking politely of the shadows how they are doing.

For my world magic all draws from the same source the soul. The different variations all are just different ways of expressing it and manifesting it. Raw Magic Practitioners like witches and wizards just take raw magic straight from their own soul or other objects people have poured magic from their soul into. Then molding it into the shape they want through words of power and will this is dangerous because if they mispronounce something or spell something wrong or just don't specifically translate your intention than it can either fail or do something you didn't intend like bad code that might blow up in your face.

Clerics, Druids, and Cultists all work through Patrons in various forms with their Patrons acting as a regulator to ensure it doesn't do something its not supposed to. For Clerics this is done by expending magical energy in their own souls through prayers, ceremonies, and vows then praying for what they want and having their Celestial channel the result through them for targeting or having specific ways to indicate targeting. Druids do something similar but they don't need to do ceremonies because their Fae Patrons draw from a pool of excess magic generated by the souls of animals they created which the Druids protect. So Druids don't have to do anything to so much generate magic for their patrons from themselves but prey and perform rituals to ask the Fae to cast specific magic and where to target it. Cultists meanwhile empower their Underworlder Patrons by sacrificing others to the Underworlders who then eat those sacrificed souls and use that power to perform magic some of which they use on Cultist request. The benefit for this is that if one of these groups mix something up a spell isn't going to blow up in their face because if it did the Patron would just cut the power before it does. Downside is if the individual wants to cast a spell even if they cast it right if their Patron doesn't sign off on it than it will just blow up in their face.