|Crystal of M3X-387|
|Out of universe information|
The Crystals are mainly found on the bark of trees. They lay dormant until they activate themselves, which makes them glow. It is unknown whether they activate when they feel the presence of a human, or if they periodically do this. They give off an unusual energy signature. The crystal can somehow make people come up and touch it, which is how they "rope in" its victims. When they do, the individual will receive an uncomfortable electric shock, knocking them backwards, and the crystal itself will shut down, because the energy is now inside the person. The crystal can also somehow control's the individual's dreams, giving them terrible nightmares, in the form of whoever touched it. Each night, the nightmares can become more and more severe until it has the capability of killing them in their sleep, most likely scaring its victims to death. The crystals likely take the dream's form of the individual's worst fear (falling thousands of feet, being eaten by a Whale). They can be transferred from person to person by touch, as it needs conductive material as transport, including Atlantis' power conduits. (SGA: "Doppelganger")
The crystals were encountered by the Atlantis expedition in 2007, in their fourth year of operation on M3X-387. Dr. Meredith Rodney McKay thought the activated crystals can by used as a self-sustaining power source. Lt. Colonel John Sheppard felt compelled to touch it, which caused an energy surge. They see the crystal was "killed off" and went back to Atlantis, not knowing the crystal energy signature is in Sheppard and that the crystal had also morphed into a doppelganger or copy of Sheppard, displaying all the character traits of Sheppard's dark side. He touched Teyla Emmagan, which passed the energy to her. That night she received a nightmare she never experienced before, which actually made her afraid of sleeping again.
However, she passed on the energy to Dr. Jennifer Keller, giving her a very unpleasant nightmare. Ronon Dex thought that it was just a few isolated dreams, until he had one himself. They discovered it was the crystal, which took Sheppard as a negative presence in the nightmares. After the crystal was able to kill one of its victims, Dr. Kate Heightmeyer, they went back to M3X-387 to retrieve another crystal to learn from it. They were able to lure the energy back to the dormant crystal, ending its terror. The planet was very likely closed off after the events. (SGA: "Doppelganger")
All the nightmares caused by the crystal takes form of Sheppard as the primary negative presence. They include;
- Teyla Emmagan; Sheppard, as a Wraith, fed on her.
- Dr. Jennifer Keller; Teyla was killed by an Iratus bug crawling out of her stomach, and Sheppard acted as if it was the "coolest thing he ever saw".
- Ronon Dex; Ran away from Wraith weapons fire, only to be knocked out by Sheppard, who later buries him alive.
- Major Evan Lorne; Thought Sheppard was a Replicator. It was apparently so traumatic, he sleepwalked and held Sheppard at gun point, threatening to shoot him until he was stunned by Ronon.
- Dr. Kate Heightmeyer; Couldn't get off the edge of a balcony, and was about to fall. Sheppard stopped Teyla from rescuing her. The severe event of experiencing it caused Heightmeyer to eventually die in real life, making her the first and only known fatality.
- Dr. Rodney McKay; Eaten by a Whale, after Sheppard goaded him to give up. However, the real Sheppard saved McKay through virtual reality, only to have the crystal inside of him.
- Lt. Colonel John Sheppard; Fought the crystal Sheppard in an empty Stargate Operations, but Crystal-Sheppard was easily able to defeat him- demonstrating a degree of superhuman strength by punching through walls and throwing Sheppard a significant distance-, until McKay was able to weaken it with an electric current caused by a defibrillator, allowing Sheppard to toss the entity through the dream version of an open Stargate, sending it back into the crystal which was connected to Sheppard.