Anti-Harry defenses

I turned and crossed the room. I sat down at the desk, a copy of the one in my main office. I put my handgun squarely in front of me. The desk was positioned directly in line with the door to the panic room. From behind the desk, I could see the entire hallway clearly.
Mag stepped forward and moved a hand as though throwing something. I saw nothing, but Gard raised her axe in a blocking movement, and there was a flash of light, and the image of a Norse rune, or something like it, was burned onto my retina. The outer edge of Gard’s mail sleeve on her right arm abruptly turned black and fell to dust, so that the sleeve split and dangled open.
Gard took a grim step back as Mag narrowed his jaundiced eyes and lifted the crooked stick. Something that looked like the blend of a lightning bolt and an eel lashed through the air toward Gard, but she caught it on the broad blade of her axe, and there was another flash of light, another eye-searing rune. I heard her cry out, though, and saw that the edges of her fingernails had been burned black.
Step by step she fell back, while Mag hammered at her with things that made no sense, many of which I could not even see. Each time, the rune magic of that axe defeated the attack—and each time, it seemed to cost her something. A lightly singed face here. A long, shallow cut on her newly bared arm there. And the runes, I saw, were each in different places on the axe, being burned out one by one. Gard had a finite number of them.
As Gard’s heels touched the threshold of the safe room, Mag let out a howl and threw both hands out ahead of him. An unseen force lifted Gard from her feet and flung her violently across the room, over my desk, and into the wall. She hit with bone-crushing force and slid down limply.
I faced the inhuman sorcerer alone.
Mag walked slowly and confidently into my safe room and stared at me across my desk. He was breathing heavily, from exertion or excitement or both. He smiled slowly and waved his hand again. An unpleasant shimmer went through the air, and I glanced down to see rust forming on the exposed metal of my gun, while cracking began to spread through the plastic grip.
“Go ahead, mortal,” Mag said, drawing out the words. “Pick up the gun. Try it. The crafting of the weapon is fine, mortal, but you are not the masters of the world that you believe yourselves to be. Even today’s cleverest smiths are no match for the magic of the Fomor.”
I inclined my head in agreement. “Then I suppose,” I said, “that we’ll just have to do this old-school.”
I drew the eighteenth-century German dragoon pistol from the open drawer beside my left hand, aimed, and fired. The ancient flintlock snapped forward, ignited the powder in the pan, and roared, a wash of unnatural blue-white fire blazing forth from the antique weapon. I almost fancied that I could see the bullet, spinning and tumbling, blazing with its own tiny rune.
Though Mag’s shadows leapt up to defend him, he had expended enormous energy moving through the building, hurling attack after attack at us. More energy had to be used to overcome the tremendous force of the claymores that had exploded virtually in his face. Perhaps, at his full strength, at the height of his endurance, his powers would have been enough to turn even the single, potent attack that had been designed to defeat them.
From the beginning, the plan had been to wear him down.
The blue bolt of lead and power from the heavy old flintlock pierced Mag’s defenses and body in the same instant and with the same contemptuous energy.
Mag blinked at me, then lowered his head to goggle at the smoking hole in his chest as wide as my thumb. His mouth moved as he tried to gabble something, but no sound came out.
“Idiot,” I said coldly. “It will be well worth the weregild to be rid of you.”
Mag lurched toward me for a moment, intent on saying something, but the fates spared me from having to endure any more of him. He collapsed to the floor before he could finish speaking.

Brief Cases, Even Hand, Page 162-163


Justine looked at me. Then her lips quivered up into a tiny, amused smile. She bowed her head to me, collected the child, and walked out, her steps light.
I debated putting a bullet in her head but decided against it. She had information about my defenses that could leave them vulnerable—and, more to the point, she knew that they were effective. If she should speak of today’s events to Dresden …
Well. The wizard would immediately recognize that the claymores, the running water, and the magic-defense-piercing bullet had not been put into place to counter Mag or his odd folk at all.
They were there to kill Harry Dresden.
And they worked. Mag had proven that. An eventual confrontation with Dresden was inevitable—but murdering Justine would guarantee it happened immediately, and I wasn’t ready for that, not until I had rebuilt the defenses in the new location.
Besides, the young woman had rules of her own. I could respect that.
I would test myself against Dresden in earnest one day—or he against me. Until then, I had to gather as many resources to myself as possible. And when the day of reckoning came, I had to make sure it happened in a place where, despite his powers, he would no longer have the upper hand.
Like everything else.
Location, location, location.

Brief Cases, Even Hand, Page 167