Time Piece

Time Pieces are tightly regulated magical artifacts that hold sway over the flow of time (presumably), and are the driving force of the "Time Rift" plotline.

Because of how easy it is to create a Purple Rift and then fail to rescue the subject, the production and use of Time Pieces is illegal in all countries except by certain authorized individuals.

Mechanism
The active ingredient of Time Pieces is Temporal Sand, which is stored within the Time Piece itself. The Sand is bound to a new, empty demiplane upon creation, and that demiplane becomes the medium of capture and playback of a "Mind Render".

Time Pieces can be reused, but the recording on them has to be erased first. The process for doing so takes about an hour of concentration. If any people or items from the real world are still inside the bound demiplane when this happens, it will become an empty void around them, but they are unharmed. The magic in the sand can also be dispelled, which collapses the attached demiplane and violently ejects anything still stuck inside. If dispelled, the Time Piece can't be used again until it can be re-enchanted.

Mind Render
When used to inflict a Mind Render, the Sand places the subject into a coma-like state, where they and the caster have a great measure of control over the mental landscape of the subject. This mental landscape is reflected by a demiplane that is created when a Render is used by the Sand, which can be accessed by making physical contact with the subject within an hour of when the Render is created. The subject of the render glows slightly during this timeframe. Upon such, they promptly fall asleep like the initial victim, and are then transported physically into the Render that forms the rift.

Playback
Once a Render ends, it is recorded by the Sand, and its demiplane maintained. If the Piece is turned upside-down while containing a recording, the playback can be experienced by entering the demiplane, using the Sand as a key. The playback similar to watching a movie of the original Render, and cannot be interacted with. The viewers of a recorded render are an ephemeral presence at best, and can move about freely within rift to view it, but are capable of little else until they leave.

The conditions that would otherwise create a Rift while experiencing a recorded Render instead simply cause it to end early and safely eject the viewer(s). If the Time Piece was broken during playback, it reforms as if it never was back in the Material once the Render ends.

Time Rifts
Contrary to what the name implies, Time Rifts up to this point in the game don't alter the flow of time directly. Instead, they're rifts to unstable demiplanes. The relative rate of time might be different within the rift, though.

Purple Rifts
While it is possible to have a completely safe Render, if the Time Piece is broken at any point during the Render, or the caster's concentration breaks, the subject becomes unstable. Their mental landscape warps, as does the corresponding demiplane, which is still being recorded. The subject's darkest fears and emotions take hold, and they become trapped in a nightmare of their own creation and must be rescued. An unstable Render such as this is known as a Purple Rift.

Purple Rifts remain for 24 hours (real time) when a victim is afflicted. If the victim isn't rescued by the end of this timespan, the rift will collapse, leaving a blank demiplane with the would-be rescuers stuck inside. The victim loses their physical form within the plane and is doomed to limbo, while the rescuers are trapped inside with a Time Piece that has lost its luster and ability to eject them. The Time Piece in the Material Plane is also blank, as if no Render or Rift had ever been recorded, until it is used again.

If individuals are pulled into a Purple Rift and are unable to escape before it collapses, they are trapped in a state of suspended time. Only by erasing or dispelling the Time Piece with which the rift was created can they be freed, forcefully ejecting them from the Render.

If a Rift is "failed", there is still a second chance. Performing a second Render on a comatose victim will instantly trigger a Rift, but also trigger its collapse. It will collapse in a much slower and more forgiving fashion, but is otherwise still dangerous. If the Rift collapses again, the demiplane is destroyed, and with it the mind of the victim.

Blue Rifts
Recently, some outside force has begun to weaken and warp the fabric of reality, causing parallel worlds to bleed through and, more importantly, the formation of Blue Rifts. These are uncannily similar to Purple Rifts, but are influenced by the mental landscape of the public rather than a single individual, as is the case with standard Mind Renders.

Blue Rifts do not close on their own, but instead have a key item or entity present within them that needs to be destroyed, removed or otherwise dealt with, upon which the rift collapses and closes as if it was never there.

Prizes
Removing items directly gained in a render is usually impossible. However, upon a recorded render closing and its subject becoming conscious, Prizes can be received. The nature, appearance, and sometimes even value of the prizes are all influenced by perceptions the subject of the render holds towards those exiting it, and are formed by the same force that creates the Render. Prizes are generally no larger than, say, an article of clothing, but can certainly be more valuable.

Since Blue Rifts aren't proper Renders, the rules for removing items/receiving prizes from them is a little different. For items to become tangible in a Blue Rift, the entity or entities guarding it, which are also manifested by the Rift itself, must be vanquished.

Writing a Purple Rift

 * Unless the victim is very down-to-earth and free of inner turmoil, their nightmares will likely take hold of the Rift.
 * That's not to say it's impossible to resist. Just unlikely.
 * Prizes should generally be received in the middle of a Rift, rather than at the end. Not a hard rule, but just an idea.
 * The victim, that is to say, the subject of the Purple Rift, is generally unseen until the very end of the adventure. However, there is generally nothing stopping them or a manifestation of their fears from playing other roles, such as an ally, a guide, an antagonist, or even all three.
 * While 24 hours are allotted in the Material Plane, it is possible for a longer time to pass within the demiplane, or perhaps a shorter time if we're feeling funky. However, care should be taken not to give the rescuers too much jet lag. One day should be the absolute maximum for extra time within the Rift.
 * When the Rift is finished, the broken Time Piece will manifest in the Rift. Touching it will send the victim and rescuers back to reality, placing the artifact in the victim's hands. Or on the healer's head. Either or, really.
 * While Prizes given to the rescuers are almost always material in nature, bias should be given towards the ephemeral when deciding what the victim receives. This can be as abstract as getting over a mental roadblock (see Gell's cookbook), or as tangible as an encouraging voice or influence within your head (Phoenix's advice to Lulu/fire magic influence).
 * Direct upgrades are also fair game if you can justify the new capability being tied to what the victim can already do (technically also Lulu, considering 🔥).
 * Maybe you decide not to give the victim a prize at all, thinking that the opportunity for them to face their fears is enough. This is also a fair thing to do, but be sure to reflect the impact of this experience in future appearances (see Xeno).

Writing a Blue Rift

 * Blue Rifts are maintained by a "core". Some interaction with the core will end the Rift, and it is up to the author to decide what the core is and how to cause the Rift end.
 * Prizes obtained from Blue Rifts must be obtained from some sort of feat, such as a puzzle or a battle. Without sufficient ground in that regard, the prize will fade upon leaving the Rift.
 * When the core is dealt with, the Rift will "collapse". This can be an escape sequence which might be cool, but might also be pointless due to an easy escape method.
 * An escape sequence is optional flavor, and can be skipped.

History
Before the Rifts started, the only known (and public) use of Time Pieces was by the High Priestess, to achieve the "PrimeTime" effect at Curios (a proud subsidiary of StarTech). PrimeTime allows anyone willing to pay a low fee of 59sp to enter the realm of their own mind and relive up to a day of their past in vivid detail.

Current Status
Known Time Pieces and their current locations are as follows:
 * Priestess has an unknown quantity (at least on) used for PrimeTime.
 * Tara's is currently being studied by Dimitri Barronmore at the Mage Guild.
 * Lulu is holding on to theirs for the foreseeable future.
 * Xeno's was given to Tara, who still has it.
 * Gell's is currently in the possession of Kim, at the Tarot Deck hideout.