Alchemy is the name given to the force at work when the four base elements combine to create reality, and is also used as a term for the study of this force. Alchemy was sealed long ago by the ancients by means of the four Elemental Lighthouses, and the seal lifted.
History of Alchemy
In Weyard's ancient past, the races, notably the Jenei (now known as Adepts) and the Exathi (a skilled race of non-Adept engineers), had proficient control over the four base elements. This was in large part due to their incredible technology, which drove civilisation to great and prosperous heights. However, their greed was effectively endless, and mastery of the four elements did not satiate their desires. Eventually, they desired even more, a quest to effectively obtain omnipotence. This resulted in the creation of Luna Tower (as it was then known), a device that was designed to absorb and harvest the light of Sol (the Sun). However, this device worked too well, and created a phenomenon akin to the Grave Eclipse, leading to the tower being renamed Eclipse Tower, and being sealed underground. Another invention was the Apollo Lens, a device hailed as the most powerful weapon of the ancient world. The great and terrible power of these devices lead to the ancient civilisation resolving to place a seal on Alchemy, using the Elemental Lighthouses to lock it away so that no-one could abuse its potentially world-destroying power. However, what they did not know was that Alchemy was the lifeforce of Weyard itself, and that sealing it actually doomed the world to eventual destruction.
The four base elements are Earth, Fire, Water and Wind (also known as Venus, Mars, Mercury and Jupiter, respectively). These combine to create all things in Weyard. These elements can be directly manipulated through the use of Psynergy and people who are able to use Psynergy are called Adepts. The Elemental Stars and Elemental Lighthouses are ancient machines that sealed away one element each, and are, prior to the Golden Sun event, the prominent sources of Alchemy in Weyard, though others do (or at least, did) exist (such as the Elemental Rocks, Lemuria and Mount Aleph). The act of releasing the seal on Alchemy is called the Golden Sun event, named for the sun-like blast of energy that was released when all four Lighthouses were lit.
Light and Dark:
In addition to the four base elements, there are two other forces (which may or may not be elements), Light and Dark. Light has not been described in detail thus far in the franchise. Dark too has not been described in detail, but is known to be a general negative force that is the diametric opposite of Light and Fire, and is responsible for making vicious monsters, such as those seen in the Grave Eclipse, the Chaos Hound and the Tanglewood's nocturnal form.
The Philosopher's Stone:
The Philosopher's Stone, also called the Stone of Sages, is said to be a source of unrivalled power and eternal life. Though the details are unknown, it has been confirmed that the Wise One is a Philosoper's Stone. Initially, the Golden Sun event was said to be the blast of light that gave birth to this stone, but the actual effects of the event were influenced by the Wise One, so it is unclear as to exactly what happened atop Mount Aleph when the Golden Sun event occurred.
Psynergy, also called Ki (せいしん Spirit) in the Fuchin Temple/Xian region of the continent of Angara, is the form of magic featured in Golden Sun. It is the ability to conjure sorcerous effects based on the elements and fueled by the spiritual power of the person's mind; a similar but distinct art exists in the form of Chi, which is the concept of harnessing the energy of one's body to achieve more physical effects.
An Adept is a person in the Golden Sun series who can use Psynergy. They were called Jenei in the ancient past. There are five types of Adepts, one for each of the elements—Venus (earth), Mars (fire), Jupiter (wind), and Mercury (water)—and a fifth non-element class called "Dark Adepts" or the "Umbra Clan" (Umbra being Latin for shadow). Adepts are usually aligned with a specific element, and thus Adepts are often classified by that element, for example, an Adept that manipulates earth or plants is referred to as a Venus Adept. Generally, Adepts can only cast Psynergy of their own elements, but spirits known as Djinn (singular: Djinni) can grant Psynergy of other elements if the Djinni's element is different from the Adept's. In modern time, Adepts are scattered throughout Weyard and tend to be located near sources of great Psynergy. Often this source is a deposit of Psynergy Stones, like those within Mt. Aleph and the Elemental Rocks. Elemental Lighthouses are also possible sources, giving birth to the Mercury Clan and explaining why everyone in Prox is a Mars Adept (Prox lying just south of the Mars Lighthouse) despite the frigid climate. The most notable exception is Lemuria, where all the city's denizens are Mercury Adepts, yet without an obvious source for this Psynergy. Alternatively, a regular person's Adeptness to Psynergy can be unlocked via direct contact with a Psynergy Stone. This method is the known source of power for Feizhi, who became a Jupiter Adept, and Eoleo, who developed the powers of a Mars Adept. One sign of an Adept involves the person's sensitivity to Psynergy use. Adepts are usually able to sense when Psynergy such as Mind Read is being used on them. Adepts can also apparently see the actual usage of Psynergy, rather than just the outcome.
Source: Golden Sun Wiki
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