Full credit for the creation of the Severing Charm is rightfully given to renowned wizarding tailor Clarke Clancy, just at the turn of the 17th century. As the son of the founder of the wizarding settlements along the English-Scottish border, Clancy – a pacifist – took up the needle rather than the wand when it came time for him to take on his father’s legacy as leader of the Scottish wizarding settlements. Though his intentions to pursue a future of needlework were not initially well received, his skill with designing suitable outerwear came in handy during the long winter months, and it was not long before the rest of the settlements looked to Clancy for their day-to-day attire. While Clancy had generally utilized Muggle methods for clothing fabrication, when the demand for his skills surpassed his production capabilities he turned to magic as a way to improve efficiency and profit. However, fearing that the brutish nature of his fellow friends and neighbours would tempt them into utilizing his spell on something other than cloth (recognizing that, should it be modified enough, it could be utilized violently), Clancy hoarded the spell until his death. It wasn’t until approximately a decade later that his daughter, Celina Clancy, rediscovered the notes on his spell among her father’s lace collection. Thus both the Severing Charm and lace garments gained immense popularity all throughout the late 17th century.

The Severing Charm, while a basic version of many other slicing-type spells, requires much more of a steady hand. When Clancy invented the spell, it was with the intention that it would easily fit into his otherwise Muggle routine. As such, any cuts that were made would have to be traced by the wand the same as they would be with scissors. Even with its mastery the Severing Charm cannot be performed with much distance between the caster and the target, and the target must always be in a direct line of sight.

 The charm works most effectively when the spell and the movement start and finish at the same time. The incantation, Diffindo (dif-IN-doh), should be said slowly, allowing enough time for the caster to trace the outline of what he or she wants to cut with their wand. The spell ends when the oral incantation does. Advanced casters may cast the spell non-verbally, allowing the cuts to be completed in a longer duration of time (so long as the caster is thinking the word).As soon as the caster begins to enunciate the spell, he or she must move his wand accordingly, tracing with extreme precision how he or she intends to sever his target. For this reason, the spell is limited to simple cuts – a maximum of two (in rare occasions, three). When first mastering the spell, anything more complex would require multiple castings of the spell. Indeed, Clancy himself never used Diffindo for anything more than to shear his fabrics into usable pieces. His daughter was the first to use it in more grandiose forms, though in order to do so she had to resort to casting the spell nonverbally so that she could properly maintain the spell for whatever length of time she was mentally capable of.

 The spell’s usage is generally limited to fabrics, cloths, and other materials of a similar nature. With increased practice, it is possible for the caster to summon enough strength so that they might capably divide foods (for example, an apple), cardboard, and in some cases, sheets of metal. While the spell is incapable of ripping or cutting wood, glass, or stone, modified versions of the spell can be used to carve or mark thicker materials. Most importantly, the spell cannot be used against other animals or other people. If this spell is aimed at a material against which it cannot cut, depending on the experience the caster, the spell may instead cut or slice the nearest appropriate object. For instance, a tree and a robe are within close enough proximity – without enough control over one’s spell, aiming Diffindo at the tree may result in a cut-up robe. As with all spells, therefore, much focus is required in order for it to be cast properly.