The Weave

In the Forgotten Realms campaign setting of the Dungeons & Dragons fantasy role-playing game, the Weave is the source of both arcane and divine spellcasting.

In addition to the Weave, there is also a Shadow Weave created by the goddess Shar; because Shar is a goddess of secrets, its secrets are kept mostly to herself.

Within the context of the Forgotten Realms, raw magic is characterized as difficult for mortals to access safely. The Weave works to protect the world from the dangers of unrefined magic while giving the ability to cast spells to magic users. Destroying the Weave results in widespread destruction. Reckless use of magic can also damage the Weave, creating areas of dead or wild magic where normal spellcasting doesn't work.^:54 It is present in everything and, until the events leading up to the Spellplague, was part of the goddess Mystra's body, who actively willed its effects. As described in earlier editions, when spellcasters would abuse magic, Mystra could cut off the spellcaster's ability to use magic.

In the history of Faerûn, the Weave has been destroyed twice. Because the Weave is inextricably bound to the deity in charge of maintaining it,^:55 killing this deity also destroys the Weave.

The first time this occurred was when an archwizard attempted to rob the goddess Mystryl (the then-goddess of magic) of her power. When he could not handle the power, the Weave became destabilized and Mystryl chose to sacrifice herself, which briefly stopped magic until Mystryl was reincarnated as Mystra.^:47

The second time this occurred was when the goddess Mystra was assassinated in 1385 DR (about a century before the time of the Forgotten Realms fourth edition campaign setting). The Weave collapsed and initiated the Spellplague, leading to several long-standing effects:^{:5, 50-52.}

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