High Magic

Elven High Magic (Arselu'Tel'Quess in elven or the Great Art of the People) is the term used to describe one of the most powerful forms of magic practiced in Faerûn. Casters of this magic are called Selu'taar, also known as the "Art's Disciples" or simply as "High Mages". High Magic spells are powerful enough to affect deities or to create world-changing spell effects. Non-elves cannot cast High Magic as they are simply unable to wield such power without being consumed by it, and in truth even most Elves are found lacking in the necessary finesse and skill.
All High Magic spells are rituals, and they frequently require collaboration of more than one High Mage. In addition, the necessary material components and timing of High Magic can be very specific. For example, in 1375 DR a priest of Vhaeraun used a High Magic spell to open the realm of Eilistraee to Vhaeraun, in order that he might slay her. The components for this mighty ritual included a certain specific configuration of heavenly bodies existing in the skies of Faerûn.
Another example of High Magic was used by Q'arlynd Melarn to wipe the name of Kiaransalee from the minds of her worshipers, thus eliminating her mortal followers. Due to the edict of Ao, any deity without mortal worship can no longer exist. Kiaransalee ceased to exist in the realm of Toril.
It was also High Magic which destroyed the ancient elven realm Tintageer and also what was used to open the gate between The Feywild and Abeir-Toril to help the survivors escape. The caster of the spell to open the gate was also consumed by the power of her spell.
During The Crown Wars High Mages of Aryvandaar caused the so called Dark Disaster and destroyed the realm Miyeritar. Another example of elven High Magic of this period was cast by the elves with the help of the Seldarine to punish the dark elves. They were turned into the drow and after that their descent began.