Petricite

Petricite is a pale, magic-absorbing stone unique to Demacia, and its story begins in the aftermath of the Rune Wars. A band of refugees fleeing the destructive power of magic were hounded by dark mages until they took shelter in an ancient petrified forest, where their pursuers' sorcery suddenly failed. Learning the fossilized trees were a natural magic-dampener, the settlers drove off the dark mages, claimed the forest as home, and mixed its enchanted wood with ash and lime into petricite. They built an entire civilization from it. The walls and monuments of the new kingdom of Demacia were raised in petricite, creating magic-dead zones that kept sorcery at bay. To carry that protection abroad, the sculptor Durand fashioned the winged colossus Galio from the stone. At the Battle of the Greenfangs, the warmages of the Arcane Fist bombarded his soldiers for thirteen days until the magic absorbed into his frame gave him life, and he crushed them before returning dormant to his pedestal. Over centuries, this defense hardened into cultural dogma. Demacia came to fear and persecute mages, and its mageseekers hunt the afflicted with petricite instruments such as the Graymark, a carved stone disk that captures and suppresses magic. Those found are exiled to slums or forced to swallow cures of ground petricite. Lux, a secret mage of the powerful Crownguard family, embodies the tragedy of the system, hiding her light even as Galio became her unlikely friend. Petricite holds a hidden flaw: it does not destroy magic but stores it. Sylas learned this while imprisoned in magic-dampening shackles, after Lux smuggled him Durand's original writings on the stone. Seizing Lux's magic on the scaffold, he blasted free and became a defiant symbol for Demacia's persecuted mages, journeying to the Freljord for allies against the throne. That same reservoir now looms beneath a kingdom whose petricite walls cannot contain the demon Nocturne, so its salvation may rest on the very magic it long tried to erase.