Sometimes in fantasy, fate is as simple as a pair of pine needles dropping on the foreheads of two newborns a month apart—one in a region where no pine trees grow. It’s a feather, snatched out of the air by a chubby little hand. A small omen that joins two players in an epic prophecy—but, even more significant than its potential to change the world is the moment in which it unites two halves, each searching for the other person who will complete them.

Imagine living your life in loneliness and then meeting your soul’s twin. Gods of light and dark, chaos and order. Threadsisters. Angels and demons. Heroes and goddesses. A princess and her shadow. Meet nine duos fated to find one another and, in many cases, to change the world.

Shefali + O-Shizuka, The Tiger’s Daughter (K. Arsenault Rivera)

When their mothers, themselves best friends, introduce the fated-paired girls at age three, O-Shizuka attempts to throttle poor Shefali. Thankfully, as they grow up together their dynamic is more affectionate, if no less dangerous: whether spoiled imperial princess O-Shizuka is roughing it with the tribespeople in the steppes for a season, or showing off her lavish garden to Shefali, their paths are crossed by tigers, demons, and various intrigues. These are the kinds of situations that would kill one or both, if the duo weren’t also—at least, according to O-Shizuka’s fanciful dreams—reincarnated gods.

But what truly bonds these two young warriors is the same thing that wove an unlikely friendship between their mothers: waging war on demons. Traveling the land together on horseback, following the signs of the growing darkness in the Hokkaran Empire, they carve out a reputation through sword and bow, while at the same time growing closer even than any prophets could have foretold. That bond is tested, however, when the impossible happens: Shefali duels with a demon, is infected with its blood—and survives. It’s one thing to be proudly connected to a fated partner when you’re both bright, shining warriors; what happens when one of you is forever tainted by the very darkness you fight?

Kuni + Mata, The Grace of Kings (Ken Liu)

“What is fate but coincidences in retrospect?” one god asks another in the first installment of Ken Liu’s silkpunk Dandelion Dynasty series. This, during a conversation in which each side pitches its desired champion to unite the kingdom of Dara: charming bandit Kuni Garu, or fearless banished noble Mata Zyndu? The thing is, these two weren’t always rivals. In the uprising to overthrow the late emperor’s ill-equipped son, they made complementary allies, the perfect combination to fulfill the angry gods’ desires to see this mortal removed from the throne.

The aftermath, however, becomes an entirely different tale, as the men once dubbed the dandelion and chrysanthemum find themselves the figureheads of opposing factions: one taking the battle to the emperor’s literal throne, the other working to eliminate his reach—their friendship uprooted by misunderstandings and politics. Are the shapeshifting gods directing the course of history, or are their prophecies and omens the divine equivalent of throwing lots and seeing where they land? Will the outcome be destiny, or complete chance?

Khai + Zariya, Starless (Jacqueline Carey)

Khai is one of thirteen babies who share a birthday with Zariya, youngest princess of the Sun-Blessed family and the House of the Ageless—so it’s not just a matter of when they’re born that links them. Nor is it only the deceptively simple test, in which one of the Brotherhood of the Fortress of the Winds drops a feather over the babies and waits for Pahrkun the Scouring Wind to direct it into the hands of the chosen infant. Yet even after being identified as the princess’ shadow, Khai must still spend his adolescence training to be worthy of that birthright. (Read an excerpt from Starless.)

But all of it—the grueling training, the heartbreaking losses, his sense of self that shifts constantly like dust stirred by unending winds—is worth it for the moment that Khai glimpses his soul’s twin. “I had found the light to my shadow,” he thinks upon looking into Zariya’s eyes for the first time, “the fire to my wind.”

Crowley + Aziraphale, Good Omens (Terry Pratchett and Neil Gaiman)

One might not guess that the angel who guarded the eastern gate to the Garden of Eden and the serpent that tempted Eve to take a world-changing bite of an apple would wind up as friends—but that’s just the first delightfully subverted expectation in Terry Pratchett and Neil Gaiman’s novel. One thing that unites angel Aziraphale and demon Crowley is an appreciation for the humans they watch over, in a manner of speaking, in their relatively cushy jobs as representatives for (respectively) Heaven and Hell. Upon discovering that Armageddon will soon be upon the mortal and divine realms, they hatch a mad plan: find the Antichrist and ensure that he grows up without knowledge of either Good or Evil, so that he may never have to decide between the two.

Too bad there’s a bit of a mix-up at the hospital, and suddenly Crowley and Aziraphale must hunt all over for an Antichrist in a haystack, if you will, in order to stop an all-powerful being in a young, undisciplined form from bringing about the prophesied destruction of the universe. Nothing like a bit of the apocalypse to turn a friendly camaraderie into a fated partnership.

Rose + Lissa, Vampire Academy (Richelle Mead)

Vampire princess Vasilisa Dragomir refuses to believe that it’s fate that kills her entire family, including her best friend Rosemarie Hathaway, in a car accident one icy night. So she taps into the element of spirit, a rare power that few Moroi vampires can, to bring Rose back to life. As someone later explains to Lissa, “The accident woke the spirit [element] in you; your fear over seeing Rose dead made it burst out, allowing you to heal her. It forged your bond. And once it’s out, you can’t put it back.” The cost of this grand gesture, however, is that Rose becomes “shadow-kissed,” and now the two are linked through a psychic bond.

Proving that fate has a sense of humor, the bond is one-sided. It’s a keen, if emotionally exhausting, benefit for dhampir (half-human, half-vampire) Rose, who is training to become Lissa’s guardian: Not only can she see through Lissa’s eyes, but Rose can also take on the negative effects of using this power, which would normally drive Lissa to self-harm, or worse. Rose’s shadow-kissed condition complicates this, as she is particularly susceptible to the darkness and could, like other shadow-kissed before her, succumb to insanity.

Alone, neither might survive. But what strengthens their friendship, as well as their bond as guardian and charge, is their willingness to draw strength from one another as needed, rather than only one of them taking on the burden.

Iseult + Safiya, Truthwitch (Susan Dennard)

Like Rose and Lissa, it’s the saving of a life that binds Threadwitch Iseult det Midenzi to Truthwitch Safiya fon Hasstrel—specifically, when Iseult rescues Safi from one of the Cleaved, a witch overpowered by their own surging magic. In Susan Dennard’s Witchlands series, the ties between people—love, hate, even minor emotions—are represented by Threads, which people like Iseult can identify by color and type of relationship. Threads can be strengthened by powerful events, such as the saving of a life, prompting those who possess these bonds to declare one another Threadfamily.

While Safi and Iseult come from vastly different backgrounds, with the former a noblewoman training for her legacy and the latter a runaway who fled the protection of her tribe, their bond as Threadsisters supersedes. This kind of shining connection is undaunted by distance, time, or meddling from outside forces like the Bloodwitch sniffing after the runaway unregistered witches. It’s unbreakable and all-defining. Six years after their auspicious first meeting, Iseult would die for Safi without a second thought—and Safi would die for her.

Fitz + the Fool, Farseer Novels (Robin Hobb)

There is no denying that the Fool is a White Prophet: He bears the signature pale hair, eyes, and skin—the latter which sloughs off after regular flu-like illnesses, revealing a darker skin tone each time. The Fool is also prone to prophetic visions, able to tap into this future projection when standing at the crossroads of key decisions.

However, sometimes the White Prophet requires the aid of another—the Catalyst, possessed of the ability to fulfill those prophecies. By contrast to the White Prophet’s distinctive looks, the Catalyst can be entirely unremarkable, which is partly why FitzChivalry Farseer does not initially believe his friend’s claims that he is the Catalyst. The Fool insists that, of the many futures he sees, the ones that match his prophecy feature Fitz standing at the crossroads—but the Fool himself cannot be the one to convince Fitz of his fate. Fitz—who has taken on and shrugged off many identities over the course of Robin Hobb’s Farseer saga—must make that decision on his own.

Nahadoth + Itempas, The Inheritance Trilogy (N.K. Jemisin)

First, there was darkness—that is, Nahadoth, the god of darkness and chaos. Then, there was light—Bright Itempas, the warmth to Nahadoth’s cold and the order to his then-sister’s disorder. While the divine siblings were eventually joined by a third—Enefa, goddess of balance and creator of life—N.K. Jemisin’s The Hundred Thousand Kingdoms focuses on the ways in which Nahadoth and Itempas are bound to one another. At one point before time was established, all three gods existed in a (mostly) harmonious polyamorous triad, which led to the creation both of their world and its mortal inhabitants. But as much as Enefa balanced her two sibling-lovers, she and Itempas competed for Nahadoth’s love—for which Itempas ultimately killed her, launching what came to be known as the Gods’ War.

Itempas’ wrath did not stop at Enefa; he also imprisoned Nahadoth in mortal form, binding him to a flesh-and-blood male body and enslaving him to be shaped by the desires of the mortals who control him. Finally, Itempas established himself as Skyfather and Master of All, setting the stage for the era in which Kingdoms takes place when young warrior Yeine is named as an heir to the Arameri family. While mortal events play out on the ground, they are forever guided by the divine power plays of the god-siblings, from the hole left by Enefa’s death to the constant push-and-pull between Itempas and Nahadoth. While these gods are immortal until they are permanently killed, as was the case with their sister, their deaths would bring about the destruction of the entire universe—and so, instead, darkness and light continue to clash, at least until Yeine learns the truth of why she was summoned to take on her birthright.

Link + Zelda, The Legend of Zelda: Skyward Sword

While every Legend of Zelda game features a different Link and Zelda, their descendants are bound by fate to play out their archetypal roles in defeating their generation’s evil. In this case, fate takes the form of a demon’s curse—with his dying breaths, the demon Demise tells young warrior Link that this will not be their last meeting:

You fight like no man or demon I have ever known. Though this is not the end. My hate… never perishes. It is born anew in a cycle with no end! I will rise again! Those like you… Those who share the blood of the goddess and the spirit of the hero… They are eternally bound to this curse. An incarnation of my hatred shall ever follow your kind, dooming them to wander a blood-soaked sea of darkness for all time!

So whether Link is the Hero of the Winds, the Hero of Time, the Hero of Light, or any other sort of Hero, as surely as his spirit lives and the goddess’ blood pulses in the next incarnation of Zelda, their destinies will be inextricably bound to fight the manifestation of that era’s evil.

Who are your favorite fated duos?