Fulmen – Experimental
One of the artifacts unearthed by newcomers to Yharnam in the wake of the Night of the Blood Moon the Tonitrus, and while the old Hunters never appreciated the destructive potential of the weapon and more modern Hunters were mostly unaware of its existence, some among the new generation of Hunters were intrigued. Hunters, craftsmen and scholars of the new workshop of the church took to disassembling this eldritch-seeming armament to discover its inner workings and find ways to replicate it, and were delighted to realize that the Tonitrus functioned on a basis of science rather than the arcane. In a matter of months the first replica Tonitrum were made successfully, much to the delight of many.
For some, however, the Tonitrus was not enough. A subset of the group that replicated Tonitrus came to question the design and limitations of the old weapon, and a redesign of a “better” Tonitrus was undertaken and completed after nearly two years of development, resulting in the Fulmen.

Much larger and more cumbersome than the relatively refined Tonitrus, the Fulmen takes the form of a hefty maul with in a weight-class just below that of a Holy Blade, with a shaft measuring 150 centimeters (4' 11”), though only the two-thirds of the shaft qualify as a handle, as the remainder is wrapped in metallic coils that connect to the head of the weapon: a plain-looking, bulky metal cube wherein the mechanical aspects of the weapon are contained. The head itself weighs close to 15 kilograms (33 pounds), demanding considerable strength for a human to use it properly, but for most part being manageable to most Hunters. The box is visually marked by fissures that run parallel to its edges, basically dividing the cube into eight smaller cubes of equal size centered around the core. The wooden handle is wrapped a thick layer of cloth, and a small, circular wooden guard marks the transition between handle and coiled shaft, with this guard likewise being covered in cloth and additionally treated with beeswax in an attempt to insulate the wielder from the weapon.
Unlike the Tonitrus, which required the wielder to actively generate an electric charge that would eventually dissipate on its own, the new workshop designed the Fulmen so that every swing of the weapon would generate charge for it, negating the need to manually recharge the weapon with use. The side-effect of this, of course, is that sustained use causes the Fulmen to build up a progressively greater and greater electric charge, making it more dangerous with every blow it delivers. Recognizing this as well as the potential safety issues associated with having to handle a highly electrified weapon after combat with no way of negating its charge besides waiting, a mechanism was added – triggered by a small lever just below the guard – which causes the segments of the head to split, opening the head and momentarily exposing the core of the weapon, discharging all stored energy at once... which, it turned out, can be a quite devastating attack. As with the Tonitrus, the charge of the Fulmen will dissipate over time if unused.