These clear crystals range from between one and two inches long (3cm to 6cm), and are often found embedded into jewelry, such as a headband or pendant. They are incredibly rare and ancient, with only a handful every being recorded in history. Some scholar theorizes they pre-date the historical period, pointing to some alien technology, while mystics speculate they were created by an advanced lost civilization. To some they are interesting trinkets, to others they are priceless treasures, to those who know their full measure they are very dangerous tools. Atlantean Crystals are like fire, when used with care and respect it becomes an asset, but when used carelessly and callously they can cause death and destruction to the user and all around them.
These items were once common among the ancient hyperboreans, especially those who practiced arcane arts. They are tools for regulating life energies, syphoning off a small bit to store so they user can tap into them when excess energy is required. When worn these crystals attune to a specific wearer, then drain 1 MP of energy from them every four hours until they store 12 MP (taking a total of 48 hours). During this time the natural recovery of MP (1 point per hour, page 176 of the Call of Cthulhu Keeper’s Handbook) is suspended. This process, while causing no lasting effect, caused the one attuned to the crystal to feel sluggish, light headed, and generally detached from what’s going on around them.
Tapping into a atlantean crystal costs the attuned user 1 Sanity point. These stored magic points can then be used in two ways. A attuned individual can access these stores MP to help fuel any magical spells they are casting. They can choose to use however many MP from the crystal to augment their own life energies stored in their bodies. Those attuned to a crystal automatically know how many MP the crystal contains.
For Example – A cultist is attempting to cast Green Decay, which required 15 MP. The cultist only has 14 MP, so they are unable to successfully cast such a powerful spell. They then tap into the Atlantean crystal they’ve attuned to, choosing to drain 5 MP from the artifact and use 10 MP of their own. They are drained 10 MP and 1 Sanity point, the crystal is drained 5 MP, and the spell is cast successfully.
These crystals can also be used to heal those attuned to them, pouring the stored life energy back into their owners to repair the damage done to their physical bodies. This healing is incredibly powerful, able to repair any damage, even allowing for the regeneration of severed extremities and injuries that can only be healed using magic. However, these energies cannot heal illnesses, diseases, or reverse the effects of natural aging. 1 HP can be healed for every 2 MP drained. Healing takes 1 round per point of HP restored, during which time the one being healed can take no action, paralyzed with incredible pain as their bodies are magically repaired.
For Example – An investigator suffers a broken arm, from a bad fall jumping out of a window while fleeing from cultists, suffering 5 HP of damage. They take off their belt, bite into it, and use their fully charged and attuned atlantean crystal to heal the 5 lost HP. Over the next 30 seconds or so they bite into the leather of the belt to keep from screaming in pain as their broken bones knit themselves back together. When the ordeal is over their arm is repaired, the 5 lost HP restored but 1 Sanity point is lost for using the item. Their crystal is drained 10 MP and has 2 MP remaining.
When used by a hyperborean, or the rare human with some hyperborean blood in them, these items have no side effects. However, when used by humans safety is not be guaranteed. Those attempting to attune to an atlantean crystal must make a POW check, and are aged one year regardless of their success. If this roll succeeds they are now attuned to it. However, that does not mean they have the psychic fortitude to endure this process. Attunement is so psychically traumatic that many would-be owners are driven mad, as a Sanity check for 1/1D10 is required. Once an owner dies (passing into negative HP) the crystal’s attunement ends, even if the owner is revived.
Lastly, if a human drained an atlantean crystal fully drained to zero MP the attuned owner must make a POW check. If they succeed they suffer a blinding headache, leaving them helpless for 2d4 hours while they recover. If they fail they suffer 1D8 HP of damage, which medically manifests as a stroke or aneurism of some sort. The crystal is then un-attuned, and can either link to a new owner or the previous owner must then re-attune to it. If they critically fail the POW check, or die from the damage suffered from a regular failure, they die. Should this happen their heads seem to burst from within as a Lesser Desh (pages 56-57 of the Call of Cthulhu Malleus Monstrorum) emerges from their shattered skulls. The creature quickly swims through the air attacking anyone within 20 yards until destroyed. While those attuned to crystal somehow know how to access the stored MP and how much power the item contains, they have no idea of the possible fatal risks involved.
