Magic is to fantasy what hot fudge is to a sundae … sublime!
When building magic into a story world, determine the following:
Will your protagonist have magical powers?
Is magic common or unusual in your setting?
Is magic feared and despised or considered desirable?
How many and which characters will possess magical powers?
Who is the most powerful?
What is the source of the magic?
What are the limits to the magic?
What does the magic cost?
If you can answer these questions in terms of your story, then you’re well on your way to weaving magic intrinsically into the world and plot. But let’s consider the last two questions in more detail.
Does magic carry a price? I think it should. At the very least it should bring a certain amount of responsibility for the character possessing extraordinary powers. If she can do anything she wants, can turn her teachers into toads and conjure up limitless quantities of hot cocoa with real whipped cream without suffering any consequences, pretty soon we’re going to have an individual out of control. Because power without restrictions leads to corruption, doesn’t it?
After the initial rush of delight, the fun fades pretty fast and suddenly we’re sated with hot cocoa. So what else is there to get into? Consider the SORCEROR’S APPRENTICE segment of Disney’s animated classic film, FANTASIA. Mickey is lazy and wants to wield magic without putting in the necessary study and practice. He conjures up a spell to animate a mop into doing his chores for him, but pretty soon the magic runs amok and Mickey lacks the skills necessary to stop disaster.
The best, most effective depictions of magic restrict it and set limits around its use. And there need to be consequences to using magic. That’s why the old fable restricts the genie in the bottle to granting only three wishes. It’s the limitation on the magic in Aladdin’s lamp that creates the fascination with this very ancient story: how will the wishes be used; how will they go wrong?
You can set any parameters around your story’s magic that you want, but once you do you’re required to abide by them. This helps build natural suspense into the plot. What if, of the three wishes, there’s only one left and now the protagonist must decide between saving her poisoned friend’s life or saving her own as the dark wizard tries to destroy her? See the dilemma?
Can you cheat through this, maybe fudge the magic a little so everything works out? Absolutely not! How can you enthrall readers if you cheat? Set the limits, push the limits, shove your protagonist through an awful choice, and let her battle the consequences. That keeps magic alive and vivid, woven through the very fabric of your story.