For some years, Calispar lived in the city of Procampur in the Vast, where he operated a secret workshop and experimented with and sold poisons and venoms. Eventually he was discovered by priests of Torm, who ran him out of town early in the Year of the Shield, 1367 DR. Afterwards, he fell in with a mercenary force, the Red Brigade, where his priestly magic and other skills came in handy. Captain Cedric Ravajar included the priest in all of the company's decisions, and the two men became firm allies, perhaps even friends.
In the Year of the Banner, 1368 DR, two Brigade scouts reported a dead-magic zone in Brynwood Forest. Cedric kept the find secret, telling only Calispar, and the two scouts disappeared shortly afterwards. Later that year, Cedric announced his retirement and disbanded the Red Brigade. Calispar and a trusted few departed with Cedric and returned to the dead-magic zone, where they reformed into the Vipers, a bandit group. They built their base, the Vipers' Nest, within the dead-magic zone, and began raiding merchant caravans going through the Glorming Pass. Calispar became a senior member of the Vipers.
Calispar had a special laboratory built at the Vipers' Nest where he continued his research. He soon found that plant-based toxins grown within the dead-magic zone were unaffected by magic, and theorized that they had absorbed the essence of the zone. He immediately saw the potential of poisons completely immune to magic.
Therefore, he contacted the Shadowkind assassins, and offered his magic-resistant poison in exchange for the deaths of a few of his enemies, including the high priest of Torm in Procampur. The Shadowkind accepted on the condition of proof of the poison's magic immunity. Calispar accepted and organized a demonstration in the nearby hamlet of Sevenecho. Autton Shadowshroud was sent to oversee the test, and met with Calispar near Brynwood on the 28th Eleasis in the Year of the Gauntlet, 1369 DR, before being taken to the Vipers' Nest. Though Calispar took precautions to safeguard the hideout's location, such as blindfolding Autton and ensuring he was alone, the priest forgot to conceal his trail, allowing the ranger Dura Gerathu to track them.
After Cedric spotted Dura on the 29th, he sent Calispar and a force of Vipers to attack and kill the ranger in his cabin in Dura's Vale.
On the 1st of Eleint, Calispar and Autton slipped into Sevenecho to poison a well, killing a few villagers and sickening more. The priests of Tymora found that their magic could do nothing to identify or cure the poison. The experiment a success, Calispar and Autton returned to the Viper's Nest to concoct more of the magic-resistant poison. However, Calispar could not make it lethal enough for the Shadowkind's purposes. Therefore he worked long and hard under Autton's gaze over the next few days to refine a more potent version.
Calispar was obsessed with completing his magic-resistant poison and his deal with the Shadowkind and thus getting revenge upon his enemies.
He was skilled in the fields of herbalism and alchemy.
He was 6 feet and 1 inch (1.8 meters) tall and weighed 200 pounds (90 kilograms). As a Talontar, Calispar's face was tattooed with black and blue whirling designs upon his cheeks and brow. His black hair was poorly and closely cut, and his eyes were black and beady.
In combat, Calispar wore chainmail and fought with a footman's mace or a Talonan ceremonial poisoned dagger. He also possessed incense of meditation and glasses of comprehending languages and reading magic.
At the Vipers' Nest, he owned a collection of books on herbalism and alchemy, and kept a planter's box of various toxic flora, and used alchemical equipment to brew and distill his poisons.
Calispar owned a journal bound in green dragon hide which detailed his experiments with poisons, among them his magic-resistant poison. With this information, a reader could manufacture many kinds of poisons and their antidotes. However, Calispar wrote it all in Dethek script to make it harder for others to learn and steal his secrets.