- "The First Men called us 'the Children', but we were born long before them."
Leaf is a recurring character in the fourth and sixth season. She is portrayed by Kae Alexander, starting in the sixth season, taking over from Octavia Alexandru, who briefly portrayed the character in season 4. She is a member of the non-human race known as the Children of the Forest.
When Bran Stark and his companions are attacked by wights as they approach the heart tree beyond the Wall that they have been searching for, they are saved by Leaf, who uses powerful magic in the form of explosive long-range fireballs to destroy the wights. During the attack, Leaf tells Meera Reed to leave her wounded brother Jojen to die, or else die with him. Leaf then uses her magic to destroy Jojen's body to prevent him from being reanimated as a wight. Leaf then tells the group to follow her into the cave at the base of the heart tree, explaining that the wights cannot follow them into the cave. As the group runs into the cave, Leaf tells them that she is one of the Children, before leading the group deep into the cave to finally meet the three-eyed raven.
Leaf sits nearby as Meera despondently regards the lands outside the Cave. When Meera rejects Bran's friendly overtures, Leaf tells Meera that her destiny is not over, as Bran still cannot defend himself in the real world and he will need Meera's help when he is ready to use his abilities outside the Cave. 
When Bran learns the truth about the White Walkers, he immediately confronts Leaf. Anticipating such a reaction, Leaf says that the Children of the Forest were at war, being slaughtered, their sacred trees cut down. She confirms that it was men whom the Children were at war with. Later, Leaf prepares the cave's defenses when Bran moves too quickly and attracts the attention of the Night King. She and the other Children fight wights with fire and the White Walkers with dragonglass, but her compatriots are killed one by one. Leaf flees with Meera, Hodor and Bran, but eventually sacrifices herself to give them more time to escape.
|Season Four appearances|
|Two Swords||The Lion and the Rose||Breaker of Chains||Oathkeeper||First of His Name|
|The Laws of Gods and Men||Mockingbird||The Mountain and the Viper||The Watchers on the Wall||The Children|
|Season Six appearances|
|The Red Woman||Home||Oathbreaker||Book of the Stranger||The Door|
|Blood of My Blood||The Broken Man||Season 6, Episode 8||Season 6, Episode 9||Season 6, Episode 10|
In the booksEdit
In the A Song of Ice and Fire novels, Leaf is a Child of the Forest in service to the Three-eyed raven. She is described as having nut-brown skin that is dappled like a deer's with paler spots, large ears, large liquid gold and green eyes which are slit like a cat's eyes. Her hair is a tangle of brown, red and gold, autumn colors, with vines and twigs and withered flowers woven through it. She wears a cloak of leaves. Bran thinks that from far away Leaf looks no older than himself or one of his sisters, but close at hand she seems far older. She has a woman’s voice, high and sweet, with a strange music in it like none Bran has ever heard, and a deep sadness.
Her true name is unknown: it is in the True Tongue of the Children, thus it is very long and also possibly unpronounceable by humans. "Leaf" is a moniker given to her by Bran.
Leaf says that she was born during "the time of the dragon", apparently meaning at some point after Aegon I Targaryen conquered and united the Seven Kingdoms 300 years ago. She is at least two centuries old because she also says that she secretly walked the world of men for 200 years observing them from the forests before growing weary and deciding to return home to the hidden cave beyond the Wall. This part of her backstory is omitted from the series, which in fact implies that Leaf in fact assisted in the creation of the first White Walkers thousands of years ago, unless Kae Alexander is playing a different Child of the Forest.
The novels have never described the Children of the Forest casting fireballs the way that Leaf seems to in the Season 4 finale - though in the scene, Leaf might be throwing some kind of volatile object at the wights (the camera doesn't focus on her hand). Whatever the case, they are described as magically powerful in the novels and have only briefly appeared in the fifth book - so it is possible that they can cast fireballs in the novels, and it just hasn't been seen yet. In the book version of the scene, Leaf lights the wights on fire using a torch, by darting around and between them with amazing speed and agility.