Spark

The spark of life (or simply known as the spark) is a vital essence in the lore of Dota 2.

Description
The spark of life is an ethereal light inside one's heart. Its glow is both a sign of life in a being and the very vitality of a being–if the heart glows with light from within, then that heart's owner is alive. Like a candle, the spark grows dim when one's life is about to fade until it is snuffed once life has perished. It can be passed down to one's descendants, so it's also a sign of kinship between individuals if they have the same spark.

In Dota: Dragon's Blood
The spark returns in the animated series Dota: Dragon's Blood. It appears to be exclusive to the divinities in this series and not a universal element, unlike Dota 2's version, so it's actually the “divine spark” in the series. The divine spark of Mene is the center of the conflict between the usurper goddess Selemene and the former (and her mortal reincarnation Fymryn who eventually has to reclaim it and her lost divinity with it), because of the divine power it holds. Whoever holds Mene's spark will become the moon deity, allowing them to become immortal, draw power from their faithful and give them power, and have access to divine powers. Unlike Dota 2's version, the spark cannot be shared in any way, which is why both Selemene and Mene (in the form of Fymryn ) had to wrest it from each other to become the one and only moon goddess. Like Dota 2's version of the spark, however, the series' version of spark is also a being's vitality and perhaps a sign of their life. Both Selemene and Mene died when the divine spark that they held was taken from them. Speaking of life, Mene's spark was essential in her reincarnation. Although she was slain by Selemene who stole her spark, Mene remained in the hearts of her faithful Coriel'tauvi, she was not forgotten. Fuelled by intense yearning and love for Mene, they continued their rituals for her, but their sacred lovemaking was another essential factor to her return, for it is a powerful magic and the highest form of worship even without a deity to receive it. Selemene may have had the spark, but it was still Mene's, so her spark answered their love for her. Eventually, her answer came in the form of a Coedwen child born after many generations to reclaim Mene's spark. As revealed by Filomena, God Empress Mirana also had a divine spark, which connects her and the Pillars of Creation with each other.

Users
Here is a list of beings and whatnot who can manipulate or exploit the spark of others or themselves.

Heroes
's is a rite of preventing death that can only be performed properly by a seasoned acolyte of the Shadow. No matter how close to death its recipient is, the ritual preserves the spark of life so that it may restart a faltering heart at the edge of death. The 's many deaths have dimmed the spark in her heart. And yet its light is bright enough to draw mothlike spirits from the realm of death to this beacon, causing an eerie of mothlike spirits that feast upon the essence of the living. Known as the spark of endless and ancient stars, the is the origin of all stars and their life in the universe. Using his staff, he sparked the fire and life of many stars. To aid him in bringing life and light to many stars, he channeled his gift to create a winged equine herald whose luminous charge set fire to many stars like he did. Bearing the spark of the Children of Light, inadvertently used his inherited spark to fuel an ancient energy forge owned by the Children by simply passing by it. With the forge alight by an echo of the Children's light, it reawakened the.

Gods
Before Nature's Prophet's seed was sown and sprouted, his mother—the woods-goddess Verodicia—infused a sapphire gem with a spark of her essence. Meant to be left in the wastes of a war-torn land, the vital essence in this gem makes it a fail-safe against the event that the cycle of life is broken in said lands by restoring its life.

Resources
According to the Pangolier, the restorative contains a spark of vitality.

Notable Holders
All creatures that are alive and not completely dead have a spark. The non-exhaustive list below shows some notable examples of living beings who still have a spark in their heart.

Heroes
Even atavistic entities like the have the spark of life.

Existing on the brink of life and death, still has a spark of life within him, albeit it is always on the brink of dimming out because of his aforementioned existence.

has a spark of life. In the next life of his resurrection, he still retains his old spark. He seeks out those who still carry his spark to further spread his teachings.

holds a spark of life in his heart that will fade when he dies. He knows the sparks of his victims are snuffed out when they die by his hand.

Proof of the 's life isn't light but rather darkness in his heart. He must eat to feed it, and in return it sustains him through the daylight that killed all of his kin.

Races
Stars are known to inherit the spark of those who conceived them, creating vast families of stars united by sharing the same spark. One example is Phoenix who inherits the spark of the Children of Light, implying that he's one of their descendants. Star lineages like the Children of Light were able to use their spark to fuel their creations with life, such as the star-forged Dawnbreaker.

Items
The can restore the spark of life in a dimmed heart, resurrecting them.

Trivia

 * The spark may have been inspired by the divine spark found in Gnosticism. Pictured as a light within a human, the divine spark is a piece of God or his divine realm that resides within all humans and has fallen from its source and into the perishable material plane. It is up to the human to reunite this piece (and themselves with it) with God, in line with escaping the material plane to achieve true eternity.