In this modern era, World War 3 would be its biggest catastrophe, now that technology is this advanced, weapons have also become advanced enough to wipe a nation out of existence, to the point that technology becomes the focal point of the war should it ever arise.
This had already become history, World War 3 indeed became the biggest catastrophe, humanity's greatest struggle, and the world's final stage because if another were to happen, no matter how long the wait, the world will end right then and there.
So a man made it so that this will never happen again, he figured out humanity's biggest weakness, which is technology, something he contributed very heavily his entire life, the moment he realized his inventions became more than just innovation, he pulled the kill switch of his inventions which are almost all the technology of the world, and left humanity with it, leaving humanity with no technology, returning them to the stone age.
This was the moment where humanity looked for more than just technology, and accidentally discovered magic.
Of course, this has adverse effects, people began a revolution of magic, attempting to overthrow the leaders, unnatural phenomena like monsters and aliens appearing out of nowhere, and so much more.
The world is in disarray again, so what it needs the most are new leaders, people who can lead this new era of technology and magic, those who can defend and fight for humanity's standing in this new reality, a reality of magic.
And they are called The Kings.