She flew low, beating her wings for speed, aiming at the legs of the battling treekeepers. Just as she was near enough to touch them with her whiskers, Embla struck Noxis with a mighty blow that cracked one of his wooden arms in two.

He bellowed in pain and Bitterblight juddered along with him. For a split second, its branches blinked out of existence.

Now’s my chance! Liska aimed herself like an arrow, tucking her wings in and using her speed to shoot straight between the legs of both Embla and Noxis, right up to the trunk of Bitterblight itself.

She hit the wooden surface with her shoulder, jarring her whole body, bouncing off again to tumble down between the roots. She curled her wings about her, keeping the heart tucked safely inside, but no sooner had she landed, she saw grasping tentacles begin to form on the surface of Bitterblight’s bark, reaching out for her, slashing at the air with their razor-blade thorns.

Desperate, Liska tried to spot a crack or knothole she could push Nammu’s heart into. A way to get it inside Bitterblight so it could do its work. All she could see was solid wood, pulsing and twitching like black jelly.

‘Where do I put the heart?’ she shouted across at Elowen, who had been lifted up in mid-air by the roots that were crushing her.

Her friend couldn’t find air to speak. But even as a tendril wrapped itself around her neck and began to squeeze, she lifted up her hand and pointed. With her last scrap of strength, she summoned a bolt of electricity that crackled out from her finger, hitting Bitterblight a metre up from where Liska crouched. The bark puckered and split, peeling back a fraction to show the withered flesh within. A small hole, but maybe just enough to get the heart started . . .

It was too high up for Liska’s griffyx form to reach. She would have to shift back and hope she had enough strength left to perform her task.

Gritting her teeth, she shrugged off her enchanted skin, jolting her body into the change. She felt her bones scream out in shock, her muscles pull and tear as they suddenly began to warp. Her heart pounded, her blood rushed. Sparks flashed in front of her eyes and her vision swam, but she could see clearly enough to notice that Bitterblight’s tentacles were on her. She could feel them wrapping around her leg even as it twisted from paw to foot.

Halfway between fox and girl, she heaved herself upright. She clutched the heart in fingers that were still tipped with claws, still shedding their coating of fur.

The tentacles cut into her calves, her thighs, burning the skin. Her whole body shook with the effort of changing itself so rapidly, but she fought to stay awake.