The building itself was connected to a magical dungeon, which was used in exceedingly rare cases to test inmates to see if they were sane enough to leave.
Known officially as The Residence for the Magically Deviant, Spellhold served three primary purposes for the Cowled Wizards.
Firstly, and most famously, it was used as a prison to house the "deviants" they found in Athkatla who were caught practicing magic without an official license. This was the role it was best known for among the common people of Amn.
Secondly, Spellhold was an insane asylum that the Cowled Wizards maintained for spellcasters who had lost their mind because of various factors. Because individuals would typically maintain their spellcasting abilities despite their impaired reasoning, they were highly dangerous and too powerful for most mental institutions to look after. Spellhold officially attempted to cure these individuals where possible, and contain them when not.
Finally, Spellhold was used by the Cowled Wizards to hold and study individuals who displayed unusual magical talents or afflictions, ostensibly in hopes of curing them or at least learning from their plight.
Individuals held at the Residence for the Magically Deviant could qualify for multiple statuses. For example, the conjurer Aphril had magically imbued herself with the ability to perceive locations across the planes at will, but was unable to turn this ability off—something that had afflicted her with crippling paranoid dementia.
Despite its ostensibly noble purposes, Spellhold was not above corruption, especially given that it was maintained in total seclusion by the Cowled Wizards, who answered to no authority beyond their own.
The cursed elven mage Jon Irenicus, as well as the Bhaalspawn Imoen, were sentenced to Spellhold for casting illegal arcane magic within the confines of Athkatla. While being imprisoned, Irenicus was too powerful to contain and killed all of the Cowled Wizards who resided there, taking over the facility to perform his own experiments. Irenicus's vampire sister, Bodhi, used the lower-floor dungeons as a hunting ground to toy with those who made it there.
It was eventually abandoned after a mass prisoner escape. Several adventuring parties attempted to loot Spellhold of its valuables but were never heard from again. It became known as an anathema to the otherwise ordered nation of Amn.
List of Known Residents
- Wanev: former Warden, driven mad by Jon Irenicus and imprisoned here
- Lonk: Caretaker
- Aphril: Inmate, cursed with permanent planar vision, driven mad as a result
- Tiax: Inmate, insane megalomaniacal gnome priest of Cyric
- Dradeel: Inmate, paranoid wizard with severe stress after trauma.
- Naljier Skal: Inmate, a bard driven insane and reduced to a child-like status
- Dili: Inmate, a young girl with the ability to shapeshift into whatever she wanted at will
- Jon Irenicus: Inmate, imprisoned for a destructive magical battle in the middle of Athkatla, broke out and took over
- Imoen: Inmate, imprisoned for fighting with Jon Irenicus at Athkatla
In an in-game cutscene in Baldur's Gate II: Shadows of Amn, before Jon Irenicus escapes from his prison at Spellhold and massacres the custodians, two of the Cowled Wizards are seen discussing how attractive Imoen is, with one mentioning his intention to "practice some enchantments" with her. The inference here is that he could have used charm person spells to force Imoen into sex with him.