Roberta Sparrow was one of the lucky ones…
(Note: This is based heavily on the film Donnie Darko, including the deleted scenes, as well as The Philosophy of Time Travel by Richard Kelly, which can be found here. I highly recommend reading it before running a Tangent Universe; seeing the film would also be very helpful.)
Time can be a fragile thing, and sometimes, without warning, it splinters completely, creating what’s known as a Tangent Universe. The term was coined by Roberta Sparrow, a woman who found herself caught up in such a universe and successfully repaired the time rift and escaped back to normal reality. Beforehand, she had been a nun, but the experience changed her so much that she left her order and became a scientist. Her book, The Philosophy of Time Travel, is very difficult to come by, but explains how things worked for her – and how she believes they’ll work for anyone else in the same unfortunate position. Whether or not she was a Chronomancer is unknown, but she is known to have been quite eccentric. (At the GM’s option, Roberta Sparrow may still be alive and able to be contacted with difficulty).
It begins with a break in time – possibly caused by a particularly foolish Chronomancer (see Chronomancer (Alternate) in the Adepts section for more info), or possibly just a glitch in this messed up world we live in. Either way, a time portal opens in the Primary Universe, and when an artifact (usually something metallic, such as a jet engine) passes through it, a Tangent Universe forms as a result.
This is where things start to get really interesting.
A Tangent Universe, while not strictly speaking “unnatural”, is very unstable. It can only exist for a few weeks before collapsing upon itself, creating a “black hole” in time that can easily unmake all existence. Luckily, though, there’s a built-in solution.
Whichever person (or family, or cabal, etc) lives closest to where the artifact passes through the portal becomes inextricably involved in fixing it. Inevitably, the artifact will come to one of them; this person is known as the Living Receiver. It’s the task of the Living Receiver to repair time by opening a new time portal and sending the artifact back through it to the Primary Universe. To this end, the Living Receiver inevitably becomes a Chronomancer (see Chronomancer (Alternate) in the Adepts section), but normally doesn’t realize this fact until caught in an Ensurance Trap (see below). The Living Receiver also (temporarily) gains enhanced strength (a +30 shift to Body) and a heightened spiritual awareness (a +30 shift to Soul). The Living Receiver is normally someone who’s unusual or eccentric, perceived as an outsider.
The other members of the Living Receiver’s family, and indeed everyone the Living Receiver encounters, are known as the Manipulated Living. The Manipulated Living will find themselves saying and doing things they might never say or do, even that they don’t understand, with the ultimate goal (though they don’t know it) of influencing the Living Receiver toward returning the artifact to the Primary Universe.
Normally there are also at least a few people who die while in the Tangent Universe. These are known as the Manipulated Dead. The Manipulated Dead gain the ability to travel back and forth through time, and to give limited visions to the Living Receiver regarding the true nature of what’s going on. However, since they’re Revenants, most of their consciousness is gone, and as a result what they say is normally pretty difficult to understand – riddles, hints and the like. A few minutes before the artifact passes through the portal, one of the Manipulated Dead may appear and inform the Living Receiver how much time is left until the Tangent Universe collapses.
Together, the Manipulated Living and the Manipulated Dead act upon the Living Receiver to create what’s known as an Ensurance Trap – a situation in which the Living Receiver must turn back time in order to reverse something terrible that’s happened. Often this means the death of someone very close to the Living Receiver – a family member, significant other, or close friend. This is the inciting incident that normally causes the Living Receiver to take up the path of a Chronomancer, if he/she hasn’t already done so.
Within the context of a Tangent Universe and “awakening” as a Chronomancer, the normal rules of Chronomancy charges don’t apply, as the Tangent Universe itself becomes the necessary major charge to roll back several weeks of time as if they never occurred. A Chronomancy skill check is likewise not required.
Afterwards, all the Manipulated Dead and Manipulated Living have vague memories and visions of what occurred, and the Living Receiver remembers it all. (This is a level 3 Unnatural check for Manipulated Living, and a level 6 Unnatural check for Manipulated Dead; for the Living Receiver it’s Level 9.)
Afterwards, unless the Living Receiver deliberately abandons Chronomancy, he or she becomes a full Chronomancer, with a starting stat equal to the number of days the Tangent Universe existed (so somewhere around 25, give or take a few points). The artifact will come to the Living Receiver again at the exact same time, but this time it’s a duplicate from the Tangent Universe, and because it contains within it an energy fragment of the Tangent Universe, that fragment can be drawn out (deliberately or accidentally, that’s up to the GM) and used as a significant charge.
Many Chronomancers begin their Chronomancy this way, and as a result, this can be a great first story to run (or a prelude) if one of your characters is going to be a Chronomancer later. Among the few members of the occult underground who are aware of the Tangent Universe phenomenon, some see the selection of the Living Receiver as proof of the existence of God, while others simply consider it an extension of the laws of nature / physics.
One addition: The Living Receiver is normally a mundane, not an adept or an avatar. Even an Authentic Thaumaturge is very unlikely, especially if there are other non-magical people living in the same house.
And another addition: The Manipulated Dead can affect the Living receiver directly, forcing him to do things if necessary to create an Ensurance Trap.
Also, the Manipulated Dead have the ability to open time portals, and the ability to create force fields out of a water-like substance.
how would a living receiver know that he was?
A Living Receiver doesn’t necessarily need to know that he is during the events of the Tangent Universe; as long as he performs his function, which the Manipulated Living and Dead will try to get him to, that’s enough. Once the Tangent Universe is over, though, only the Living Receiver retains complete memories of it, and at that point he’d be unable to avoid figuring it out (since he’d remember using time-reversal powers).
An addendum: Living Receivers will often allow themselves to be killed when the Artifact reappears in the Primary Universe, to ensure that a Tangent Universe doesn’t happen again. (And also because of all the horrible things they remember happening to their loved ones in the Tangent Universe, either directly or indirectly the Living Receiver’s own fault in most cases.) This isn’t strictly necessary, though.
Also, the Manipulated Dead are more powerful than the Living Receiver.