Silver Key

"Don't doubt. Don't be afraid. And know. Knowledge will save all the keyword"

The Silver Key is a type of living organism that feeds on humans, consuming information. During a state of inactivation, it's contained inside some sort of cube. To achieve it, one has to recite the specific line while staying near the Key: „Don't doubt. Don't be afraid. And know. Knowledge will save all”. It works like some kind of keyword that, if said aloud, results in affixating the Silver Key to that person. After that happens, reciting the line by someone else doesn't cause the parasite to change its host. Once activated, it travels through parallel universes, rewinding time and imprisoning the parasitized by it individual inside loops.

In order to fulfill the release conditions, its host is forced to gather information. The Silver Key gives them some special skills, and along with subsequent loops, they gain more control over the parallel universes, though it's possible that the Key will break at some points and temporally limit their power. Once the parasitized person manages to collect enough information to satisfy the Key, it starts searching for better grounds, and a better host. To do so, it gives their current one an ability to open up a portal that leads to a different universe. If someone were to go through that „door” and remove the Key, it would cause the parasite to leave its host.

Appearance
The Silver Key is a small life form about the size of half of a hand. It's made up of two circles that emanate light, a blue one, and a barely visible, smaller yellow one, that's inside the bigger ring. There appear to be two blue rods within the outer circle, that form the shape of a „plus”, and a third one, that crosses it diagonally. Outside the rings, there are two blue, arched shapes that seem to be sticking out of the diagonal rod. The bigger circle appears to be made of two snakes, eating each other's tails. They strongly remind Ouroboros, a symbol of infinity or cyclic destruction and renewal, which may be a reference to the loops.

The Silver Key stays invisible to other people aside from its host, unless they „produce it”, which results in the Key flying low above their palm. The only exception is when it's inactive, since in that state it stays within a transparent cube, visible to everyone.

History
During the evacuation from Liu-An, the Silver Key appeared aboard D.Q.O. as property of one member of the crew: Raqio. Although they were the owner of the Key, they kept it in a state of inactivation, and it was Player who ended up being parasitized  by it. When the ship was passing through the Allacosia system, Setsu were hit directly by flying debris and doomed to die. To avoid this, Player placed by them Raqio's Silver Key and told them what the keyword is. And to make it possible for Player to do that in the first place, in a different loop, Setsu gave them the Key. When  Player fulfilled the release conditions, Setsu were the one who went through the „door”, freeing Player from the cycle. Once Setsu gathered enough information, they persuaded Manan to enter the „door”, likely making her the Silver Key's next host.

Trivia

 * The Silver Key is named after/inspired by H.P. Lovecraft's "The Silver Key".