The Lebenskünstler is a device which seems to be nothing more than a pocket watch to the naked eye. In truth, it is a highly versatile device whose function is synonymous with the Reishi Henkan-Ki: the conversion of physical matter (Kishi) into Spiritual Matter (Reishi). While a virtually useless concept when applied to the Soul Society and Hueco Mundo, both of whom are entirely composed of Reishi, the conversion of physical mass into usable energy for a Quincy within the bounds of the World of the Living is an invaluable asset which can easily tip the tide of battle in his or her favor.