Legacy Weapon

The Legacy Weapon is an ancient and legendary artifact of Primordial origin. Historians and scholars recognize it as a device composed of several other artifacts for the express purpose of being able to destroy the Gods. It first appears in writings referring to the Dawn War, the ancient conflict between the Primordials, who sought to destroy their virgin world, and the Dawn Gods, who sought to protect it. The weapon was meant to be a manifestation of all of the Primordials' power, consisting of all four elemental energies, as well as certain concepts: life, death, mortality, time, and space. 
The existence of the weapon itself is a much debated on fact; many say that the Primordials themselves were powerful enough to battle the Gods without the aid of a weapon that would serve as a conduit of their power. However, most do not even know of the artifact at all, real or otherwise, as it is not commonly written on, debated, or discussed. 
The Legacy Weapon re-entered relevancy in the mid 400s AT as the main focus of Narael Tarquin's plot to destroy the Gods. He poured through ancient texts, rumors, letters, books, runes, spells, and rituals for decades, using chronomancy to grant him plenty of time to study the artifact. Eventually, he crafted his own iteration of the Legacy Weapon, consisting of the following:
* Fallen Star 
** The Remnants of the Fallen Star sent by the Dawn Gods to destroy the Second Ruinvasion from the Purged Lands
** Purpose: Container of Godlike Essence, Capacity to Banish the Gods from their Planes
* Mirror of Regret
* The Spark
** Ancient and purely energy Primordial manifestation of Love, Creativity, and Initiative
** Purpose: To ignite the weapon
* Stone of Finality
** Primordial manifestation of death, decay, and nothingness, Capable of bestowing Eternal Slumber
** Purpose: Part of Infinite Loop of energy with its counterpart, Stone of Progeny
* Stone of Progeny
** Primordial manifestation of life, growth, and being, Capable of bestowing Eternal Life
** Purpose: Part of Infinite Loop of energy with its counterpart, Stone of Finality
* Breath of Levity
* Roving Eye
** Mysterious and alien aircraft, giant spherical shape, capable of travelling through the air and to different planes
** Purpose: To channel the energy of the Legacy Weapon to different planes as a focusing lens
* Altar of the Helix
* The Black Lotus
* Energized Protodermis
* The Monolith
* Heart of Halcyon
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* The Cube
** Gargantuan black cube, origins unknown, caused the Obliteration in the early days of Civilization, wiping out an entire kingdom 
** Purpose: The Engine of the weapon, capable of maintaining huge amounts of energy and producing raw destructive power
* Veiled Mist
** Purpose: To blur the fabric of reality, to kill a god requires a rejection of rules
* The Flesh of a Mortal
** Literally the flesh of a mortal, one created by the gods and given life by the primordials
** Purpose: To imbue the gods with mortality
Spoilers for the End of Legacy (Campaign)!
The Legacy Weapon, as Narael envisioned it, was fraudulent. The weapon itself existed, it had serious power and potential to cause damage, but it did not have the capacity to destroy the Gods. He had realized through all of his research that the power of the Gods did not lay in their immense strength, immortality, and dominion over entire planes; rather, it lay in their followers. So long as people believed in the Gods, believed in their power, their powers were made manifest. To be sure, even if a God had not a single follower, they would still be incredibly powerful beings, capable of dominating planes and ; but faith made them immortal. He could not destroy the Gods with a simple weapon; no matter how much power he put behind it, if the people believed in their Gods, they could never die. And so, he would have to destroy the faithful. 
Narael's entire plan hinged on making people believe that the Legacy Weapon was not only real, but a tangible threat, and capable of destroying the Gods. He had to make not just the followers, but the Gods themselves worry that they were in serious danger. So, he fabricated the list of artifacts needed to make his version of the Legacy Weapon; the methodology in the crafting of his version of the weapon was there, it was sound, and researched meticulously enough to sound authentic. He carefully guarded the secret of his search and crafted a layer around his master plan: destabilizing the realm. This would serve to function as a smokescreen for his activities. In truth, there were two layers: Destabilizing the realm was both the first layer of the fake plan and actually his ultimate goal to destroy the faith in the Gods; as part of Narael's plan, it existed as the fake first layer to protect his "true" goal, to assemble the Legacy Weapon, which in itself was a bluff to erode faith in the Gods, mainly through the quest to find the Legacy Weapon pieces and through destabilizing the realm as a whole. As an additional element, he plotted to have mortals emerge as heroes to combat the threats he placed in the world, individuals that regular people could follow and place their faith in. The idea was that if mortals could place their faith in others like them, if they could trust their own kind more than the Gods, then it would serve as a "Legacy Weapon" in and of itself. This plot emerged as the main cast of Legacy (Campaign): Christine, Cedric, Revan, Gavros, and Vicora, who were to be Narael's "heralds" of the new world, whether they realized it or not. 
The entire struggle between Primogeniture and the Order of the Daffodil during the Legacy Conflict was built upon that lie, that the Legacy Weapon could destroy the Gods. Millions of lives were spent based on that lie: countless of Narael's family members, his loved ones, friends and allies, numerous innocents; all churned into the machine that was Narael's Legacy Weapon. 
And through it all, Narael kept a constant cool, collected façade that this weapon was real.