Among the Vrac̆, Thaddeus Vrac̆ is probably best known for the remarkable and detailed illustrations he added to the family’s grimoires.  He specialized in Silvidae magions, and left numerous detailed depictions of them, as well as medicine making processes.

Although he specialized in plant-life, one of Thaddeus’ best known discoveries relates to the mixturidae Līmāx funginus. The Līmāx funginus can cause quickened decay, but Thaddeus found that the mucus produced by its slug-like foot can slow the decay significantly. The mucus was found to be useful for the reduction and prevention of fungal decay in general, and became an important ingredient in the Vrac̆ inventory. Thaddeus ascribed the inspiration for studying the Līmāx funginus to his daughter, Milagros (1241-1319), then only a child. At 14, Milagros already joined her father's research, together they continued the study of the Līmāx funginus, and numerous other magions.

Note: at this point in history, surnames were not generally used, however, the moniker “Vrac̆”, meaning “healer”, was used for early members of this family line, and later members did adopt it as a surname. Therefore, while not entirly accurate historically, the 'surname, given name' convention has been kept for early members of this line for convenience.