Nyx Crystallis pressed her palm to the black stone at her realm's heart and felt her throne fail her. She was growing it from a living seed of crystal, feeding it moonlight so it would one day channel the moon's power across her whole realm. But crystal grew slow. To feed it faster, she needed rare gems from the deep caves, and to find those gems she needed her bats. This morning her bats were dying. She climbed to the roosts in the high tower. The smell told her first: sour and wet, like rot. Her night-flyers hung from the beams in tight rows. Half of them trembled. A gray film coated their wings, thick as mold. When she lifted one, it barely gripped her finger. Without keen scouts, she was blind to the caves. Without the caves, her throne would stay a stunted sliver forever. A red-haired sprite in a black corset dropped through the tower window on pastel wings. She was Nyx's healer, small enough to sit in a cupped hand, sharp enough to argue with a queen. She landed on a rafter and touched a sick bat without flinching. "Blight," the sprite said. "It came in on damp air. It spreads by touch. Burn the roost and you kill it." "And kill my whole colony," Nyx said. "No." The sprite crossed her arms. "Then find a cure by nightfall, or you lose them all anyway." Nyx thought of the jeweled tree in her garden, the one with cascading branches and berries that shimmered like cut stones. Its fruit held clean moon-sap. She had never fed it to bats. She had nothing else. She needed the highest berries, and she could not climb fast enough. So she whistled for the pegasus. The luminous mare landed in the courtyard, rainbow wings folding like colored glass. Nyx swung onto her back. They rose along the tree's hanging branches. She stripped the brightest berries into her skirts until her hands bled from the sharp leaves. Back in the roost, the sprite crushed the berries into a paste. Together they smeared it on wing after wing. The gray film hissed and curled away. One bat stretched. Another. By the time the moon rose, the trembling had stopped. The colony lived. Nyx sagged against the beam, exhausted. "It worked." "It worked once," the sprite said. She held up the last berry, alone in her palm. "You stripped the tree bare. It won't fruit again for a season. And the blight is in the air now. It will come back." Nyx looked at her weak, healing bats. She had saved them. But she had spent her only cure to do it, and she could not buy another for months. She stood. The caves would have to wait. Before she fed one more grain of moonlight to her throne, she had to find where this blight was breeding — and stop it at the source.