Molly shield

Captain Turtleneck drew one of the seashells from his belt, murmured something to it, and gave it an expert, effortless flick. It sailed through the air and landed only inches from my invisible apprentice’s toes.
“Oh,” Lea said, setting her mouth into a pouting moue. “Pity. She had such potential.”
I gave my godmother my most furious glare and sprinted forward.
The shell began to glow with a urine-colored light.
It had worked for Morty. Maybe it would work again.
I flung myself at Molly, focusing on protecting her, and I felt myself slide into her, merging and mingling from the soles of my feet to the crown of my head. (Which hardly made sense, given how much taller I was than she—one more example of the way physics doesn’t necessarily apply to spirits.)
I suddenly felt utterly exhausted, frightened, and at the same time in a state of euphoric exultation. I could feel the various illusions dancing upon threads of my will, demanding complete focus and concentration. My legs and feet ached. My ribs ached. My face and shoulder hurt.
And then I felt myself choke, then wonder what the hell was happening to me.
It’s me, kid, I thought, as loudly as I could. Don’t fight me.
I didn’t know what the seashell would do, but there wasn’t much time to get particular. I extended my left hand along with my will, and murmured, “Defendarius.”
Blue energy suddenly blazed up around Molly and me in a sparkling sphere.
The seashell shone brighter and exploded into a sphere of pure white fire, as hot and fierce as a microscopic nuclear warhead. It lashed against the blue sphere like a bat hitting a baseball. The sphere went flying, taking us with it. I braced my arms and legs against the sides of the sphere, straining to hold it together. Without my shield bracelet, I wasn’t sure how long I could keep it up.
The sphere struck a car and bounded off it into the wall of the building. Its path had us careening tail over teakettle, but our braced arms and legs kept us from smashing our head against the sphere’s interior. We wobbled and rolled into a corner of the lot, and I realized dully as I looked around that Molly’s illusions had vanished. My bad. The strength of the shield had cut her off from them and ended her ability to keep them going.
I looked up to find the turtlenecks advancing on us in a crowd, and I dismissed the sphere, landing in a crouch. I gathered more of my will together and swept my arm from left to right with a murmured word, and a second curtain of blue fire sprang up between me and the oncoming bad guys.


Ghost Story Chapter 22, Page 250-251