Megas Drepanon (WotUs)

Megas Drepanon (literally: Great Sickle/Scythe) was the symbol of Kronos' power and the Scythe given to him by Gaea to kill his father: Ouranos, Megas Drepanon seems to be a weapon capable of mortally wounding and even killing a God although it varies between Gods and even depends on the object(s) that anchors them to the modern world, Megas Drepanon seems to be indestructible on a material level as it transforms between elemental forms (Solid and Liquid, possible even a Gas form) depending on the state of Kronos at that present time and so long as Kronos lingers this weapon cannot be killed and vice versa while incidentally it is also the only God-slaying weapon that cannot kill Kronos himself. It eventually appears in the Wrath of the Usurped series.