What is your fantasy setting's ultimate act of magic?
It doesn't have to be a spell, necessarily. It just has to be some thing to do with the magic of your world.
Warhammer and Drain Magic
In Warhammer Fantasy, old world, one of the ultimate spells - and arguably the ultimate spell - is the one that drains magic from the world. Magic is carried on the wind from an ancient portal on the north pole that is constantly spilling for chaos, and Ulthuan - realm of the high elves - hosts a maelstrom that drains magic back out, like an everflowing bathtub. They can wield this on a small scale with their High Magic, and in its various incarnations it's an ultimate dispel, makes casting magic more difficult or impossible, kills magical beings and banishes demons. The ultimate act of magic is the denial of magic, to yourself and to others, a reflection of the kind of attitude the greatest mages of the setting - the high elves, wood elves, slann - have towards magic as a force in their world. It says so much about the setting.
Frieren and the favorite spell
In Sousou No Frieren, there is no one ultimate magic, no ultimate defense or ultimate attack. The magic that matters to you as a person most is the ultimate magic, whether it's in what it does for you or - more commonly - how it represents your connection to others. Frieren uses her teacher's favorite spell - one that conjures flowers - to conjure the favorite flower of her deceased party leader, one she realized only too late that she was in love with. She has a deep abiding love for the petty strange weird spells of humanity because she was there for the birth of magic among humanity, and this is how she has her power in the narrative of Frieren.
D&D and Wish
Hate to mention it, frankly, because it's boring. Wish is simply "magic that lets you do anything." The ultimate power fantasy of a power fantasy, it largely has been defined through the years as 'can let you play a character longer', 'can raise your stats' and 'can let you win at the economy.' One of its most powerful expressions is 'can cast magic that is otherwise denied to me by the arbitrary class system.' Only a subset of characters even gets Wish as an option and it's always been a huge problem and headache, but never removed because it is, for better or worse, the ultimate expression of what the game is and what it's saying, down to 'wizards rule everyone else drools.'
Kamehameha
How is that the "ultimate spell" of Dragonball, Freyja? Surely it's one of the forms, or other techniques like spirit bomb?
No. It's Kamehameha. Used in any form. Reliant on the core of Dragonball's entire philosophy of personal strength. Magnifies the power of the user, based on the user. Crosses generations, denotes passing of torches, literally creates the classic beam struggle that represents clashes of people and their ideals. The spirit bomb is merely part of the philosophy of Kamehameha, an expression that being personally strong isn't always enough, but strength used for others might be; the strongest Kamehameha is always the one used for the sake of both the self and others. The personification of pure strength of self, used selflessly.
It is the essence of what dragonball is, given pure expression, defining the story far more than any other technique. Strength of self and selflessness.
What is my ultimate spell?
For a setting me and my wife to be @quakefultales are making, we talked about this. What are we doing and saying? We want a cosmopolitan fantasy setting that involves mass cooperation in the face of impending disaster. We landed, after a brief discussion, on the ultimate spell being understanding. Magic in this setting is (probably) going to reflect real life cognitive dissonance and competing ideas, inherently contradictory mutually and in the self, more an artistic or philosophical expression than a coherent set of physical replicable rules. The ultimate spell will be fully understanding someone's magic expression. To comprehend them, essentially, as who they are as individuals, fully and utterly. To See. To be seen. It will (probably) be characterized as a form of perfect defense against their magic while active.
What is your ultimate magic?
