Baba Yaga

Baba Yaga is a mythological figure in the Slavic nations.

She is depicted flying around in a mortar and wielding a pestle. She also has a house that walks around on bird legs.

The Soviet Invasion
During the Cold War, the Red Army set up a base in Siberia, near the village of the Remnants. The Soldiers were seeking a way to weaponize a flower with hallucinogenic properties, taking a, Serafima into the Vale to research a way to counteract the pollen in the air to make it easier for them to work. However, only one man returned. Saying they had been attacked by Baba Yaga, who made them "do things" possibly hinting that the witch had made them kill each other.

Modern Day
Years later, Lara Croft travelled to Siberia in search of the lost city of Kitezh. She intercepts a message from Trinity about a Native being wounded in the sawmill. She dispatches the Trinity forces in the area and meets a young woman named Nadia in the Soviet installation. Nadia tells Lara that she was ambushed by Trinity while trying to find her grandfather, Ivan who ventured into the WIcked Vale to kill the witch, Baba Yaga, in retaliation for her killing his lover, who was the biochemist who the Soviets brought into the Vale. Wounded, Nadia is unable to go after her grandfather, so she asks Lara to go in. Lara goes to the Vale, seeing totems to the witch. Lara ventures further in, passing through a group of flowers, and begins coughing, as she passes through, her vision becomes hazy and suddenly she begins to see strange things. Including Baba Yaga's walking house. She sees her father chasing after him, until she witnesses him shoot himself, though his head is that of an animal skull. Lara is then attacked by Baba Yaga. who traps her in a pit, siccing demonic wolves on her. Lara fights them off, but the witch attacks her again, Lara jumps into the river to escape from the witch.

The Truth
Lara gets out of the river a ways down, and is called by Nadia, who thought Lara was killed by the witch. Lara says that she thinks she was hallucinating. Nadia tells her that there is a flower in the valley that can cause visions, though it's effects aren't very potent. Lara comes across a boiler, which smells like the flowers. She realises that Baba Yaga is not truly a witch, and is in fact just a human who is refining the pollen and weaponize. Lara finds the notes of Serafima, fiding a recipe to counteract the pollen.

Lara finds the ingredients needed and mixes the antidote together, giving her two doses. She returns to the vale taking the antidote before she passes through the area with the flowers. The antidote works, and Lara sees the world for how it is, and sees that there was nothing supernatural, and that the pollen had simply made her imagine the supernatural elements, seeing that Baba Yaga's walking house was in fat just a cable car, which had been modified to make it look like it had legs. Lara and Nadia take the cable car to the temple, where they find Nadia's grandfather. Nadia gives him a dose of the antidote, and stays with him while he recovers, whilst Lara goes to face Baba Yaga.

Lara journeys to the centre of the Temple, where she encounters Baba Yaga, who causes her to drop her antidote, meaning Lara has to face her whilst under the effects of the pollen. As the battle continues, Nadia calls Lara and tells her that her grandfather is awake and told her that the witch didn't kill her grandmother, but in fact is her grandmother, she asks Lara to not kill her.

Lara manages to defeat the witch, who continues to act aggressively. Lara lays down her weapon and tells her that she knows who she is, and that she doesn't have to live as she is anymore, Ivan and Nadia arrive, Serafima is in shock, as she had been told that Ivan had died, Ivan rushes to her side and wraps her arms around her.

Nadia realises that Lara knew that her grandmother was the witch beforehand, and realises that it was obvious in hindsight. Lara wonders if Serafima will ever truly be able to return to the outside world after playing the part of Baba Yaga for so long.

Trivia

 * Baba Yaga's method of using pollen to cause hallucinations in her enemies is very similar to the character Jonathon Crane A.K.A Scarecrow, who is a nemesis of Batman.
 * Lara had realised Baba Yaga's identity long before Nadia had told her, she even attempted to tell Nadia when she discovered the antidote recipe.
 * Baba Yaga was clearly Russian, as the Remnants who were of Greek origin would not be familiar with the tale of Baba Yaga.
 * Baba Yaga clearly had knowledge of chemistry to weaponize the pollen.
 * She was clearly motivated by revenge for a perceived loss.