Percy
"That's impossible," said Ron.
"And wizardry isn't?" Thalia asked. "It's true. I'm a daughter of Zeus, and Percy is a son of Posiden."
"It's not possible," said Hermione.
Thalia squinted her eyes like she was concentrating hard. Lighting flashed and hit a tree nearby, lighting it on fire.
"Alright," Harry said, "We believe you."
"Well," Thalia said impatiently. "We need a plan to get them out."
I thought hard. "Well, Annabeth said to come back at night."
"Okay," Harry agreed. "We'll do it tonight."
"Sorry to interrupt," Ron said innocently. "but, THE TREE IS ON FIRE!"
"Aguamenti," they all yelled before drenching the tree in water.
"There's a window in the basement," I suggested. "We can get them out through that."
Thalia wasn't so sure. "I don't know if they can fit through that, Percy," she said. "We can try an open attack?"
"Wait," I said. "Let me see something."
I put the tip of my blade to Hermione's forearm.
"What do you think you're doing, and why doesn't it hurt? I don't mean to say that I'm complaining."
I waved it around her arm, then slashed through her waist. Nothing.
"Our weapons won't work on you," I said.
"Why not?" Fred said, or was it George.
"His sword is celestial bronze," Thalia explained. "It's mined by the Cyclopes, tempered in Mount Etna, and cooled it in the River Lethe."
"Even I hardly understood a word of that," Hermione said.
"Okay, that doesn't matter," Thalia said. "We have to make a plan."