One quiet autumn day, a stranger came to the city. His travelling cloak was dusty black wool, lined with something strange that seemed to change colours as he walked: green to purple to vivid orange to a gold that looked real and back to that trembling, shifting green. He strode through the square one market day with his riding boots clicking a drumbeat upon the cobblestones, leading his limping horse by the reins, and when he asked where he could find help they sent him into the forest. There was a little path there, a long and winding strip of land where nothing wanted to grow, and at the far end of it stood a house with leadlight windows and a tall rickety chimney where people could always see strange wisps and lights. The grains of magic from the smoke crystallised on the rim of the chimney pot and the world up there was different, it was playful and unexpected as though it didn't want to listen to the rules of nature obeyed everywhere else. There were rainbows up there on foggy days, crackling thunderclouds at midsummer, perfect snowflakes in May. The house was always surrounded by flowers, red velvet roses and climbing honeysuckle, even in winter, even when the frosts were too much for the rest of the forest and it lay silent and still as it waited for spring.
When his horse's injured foot had been healed by the witch's salves and spells the stranger left and he was never seen in the city again – but the witch always said bitterly that he'd never gone, not really. He'd left something behind, and so in a way he'd never left at all. He was tied to the little house in the woods as surely as the ivy that clung to the crumbling brick walls.
Nine months later the witch had a son and nobody knew why. Witches never had sons. In living memory there had never been a single one, but there he was: a tiny little thing with enormous dark eyes and miniature fingernails, wailing or gurgling or giggling to himself in the corner of the room when the people of the city went to see her for their spells and potions and petty little curses. His name was Linden after the tall trees outside and the linden flower tea the witch had craved while he was growing inside her: linden to help vomiting and a regret that was almost unbearable.
Little Linden grew tall, like his namesake trees, slender but strong, and the witch put him to work cleaning the house, fetching things from town on the back of the old donkey (who used to be a neighbour who refused to pay his debts), racing around the forest with a lantern in his hand trying to gather all the herbs and plants she needed to be picked under moonlight to increase their potency. Every year on the birthday she never acknowledged, Linden asked if he was old enough to learn magic yet, and every year she shooed him away like an irritating little bluebottle until one day, the day he turned thirteen, she hit him with her broomstick instead when he asked and spat out, "No!"
He didn't cry, he never cried. He just rubbed the sore bit of his arm and asked, "Why?"
"Because you're the son of a cheat and a liar and you can't be trusted with magic."
"I'm the son of a witch as well," Linden said defiantly, and she charmed her broomstick to chase him through the house and out into the forest.
After that he stopped asking. Instead, he waited for the few hours the witch was sleeping or out and began to teach himself. He read all her incantation books, sounding out the unfamiliar words carefully until the magic started working, and then he took a quill and some paper and began to write his own spells: magic to enchant the broomstick with invisible padding so it didn't hurt when it hit him, magic to make him understand what the cat was saying when it yowled and purred, magic to banish the pain of the woodland animals whose guts and hearts the witch ripped out of their living bodies for her potions and augury.
Summers passed, and winters too, and by the time Linden was seventeen he could make the church bells ring three towns away with a wave of his hand, he could light up the sun in the middle of the night, he could change himself into a bird and fly between the trees – fly away, he always told himself, fly away and be yourself. But there was a tugging in his chest like a narrow noose that constricted tighter and tighter around his heart the farther he flew from the little house, and he knew he was bound to the witch for life.
Then one day in June when he was asking the trees for flowers that the witch usually took by force, he saw a man in a black and shimmering green cloak ride past on a tall chestnut horse. The witch often had visitors, people asking for help to cure someone or curse someone, so he dwelled no more on it until he heard galloping footsteps and saw the horse disappear back the way it came, this time without the rider. He gathered up his things and went back to the house, murmuring a spell to make his feet silent on the gravelly path as he crept up to the open door in case there was trouble he would be able to fight better if he went unnoticed.
There he saw the rider, the shimmering colours on his cloak now turned a dull steely grey, flat on his back on the old oak table with his head hanging over the edge and his long black hair dangling almost to the floor, dead eyes open and staring blankly at Linden upside-down. There was a discarded dagger on the table beside the body, ruby-red with blood on its gleaming silver blade, and the witch was red up to her elbows and mad in the eyes as she used his insides for scrying.
"This man is your past and mine," the witch said when she saw Linden standing in the doorway. "He'll tell our future as well."
Then, as calmly as the forest stream bubbled over the rocks and pebbles on its bed, Linden the witch's son turned his mother into a bird that he crushed lifeless in his fist. He did it over an empty flask to catch the blood because he'd read somewhere that only the blood of a witch can bring the dead back to life.
"I'll make my own future," he said to the cat, and began gathering the ingredients.