The Ouroborean ambled around the corner. It had its arms out, running its fingers along the shelves on either side, and Alice could see tiny sparks of magic flowing out of the books and into the creature’s black-and-silver body.

“Hello, Alice,” it called, voice mocking beneath the static.

She hefted the spear, drew back, and threw, pulling Spike’s thread as tight as it would go. The weapon sang through the air, fast as a bullet, and hit the Ouroborean in the chest. It sank deep, and the creature staggered backward.

Dex was already handing Alice another spear, and she threw again, before the creature could recover. This time she hit the Ouroborean in the shoulder, spinning it into a bookshelf, which wobbled dangerously at the impact. The third spear sank into its stomach, and the fourth caught it in the arm and continued on to embed itself in the wood, pinning the thing in place.

Alice hurled the fifth spear, but the creature had recovered from its surprise. The Ouroborean raised its hand, the spear impaling it through the palm, point stopping bare inches from its blank, eyeless face. Then, all five spears dissolved, liquefying and flowing into the creature’s black skin. They left no wounds behind. Dex grunted.

“Continue to struggle, by all means,” the Ouroborean said. “It is in your nature, clearly.”

“How do you know what’s in my nature?” Alice said as Dex panted for breath.

“Time and distance mean nothing on the other side of the mirror,” the Ouroborean said. “I learned a great deal about you when you visited the Palace of Glass, Alice Creighton.”

“You all right?” Alice said to Dex, taking a step backward.

“I believe so.” Dex’s first step was a little unsteady, but she recovered quickly.

“Then run!”

They ran. The Ouroborean pushed itself off of the bookshelf and followed, its loping stride closing the gap between them with terrifying speed. Alice stopped at the next intersection to grab the shelf on one side and pull it down in an avalanche of books and dust. The Ouroborean stumbled as the heavy shelf slammed into its shoulder, and it brought one massive fist around in a blow that cracked the shelf in half and sent splinters of wood flying. Dex handed Alice a pair of dagger-length spears, and Alice sent them zipping over the wreckage just as the thing got up, snapping its head back as they sank in where its eyes ought to be.

“Keep going!” Alice said as the creature climbed over the wrecked shelf. “Left! Around that corner!”

Dex was panting, and the dust-choked air burned Alice’s throat. They were in the back of the library now, dodging between clusters of bookshelves, each its own tiny world with a portal- or prison-book in the center. Alice pointed to one.

“In here!” Alice shouted. “Squeeze between the shelves!”