Katia's rare crossbow bolts that strip a god's invulnerability and pin the deity in place for a few crucial seconds.
The Bolt of Ophiotaurus is one of ten prized 'Danforth bolts' — crafted by Katia — that can strip a god's invulnerability and hold the deity immobile for about fifteen seconds. Long husbanded by Donut as the party's one lever against the invulnerable fire god, they finally pay off in the eleventh-floor arena: firing her Scorpion's Bite crossbow mount, Donut buries two bolts squarely into Emberus's smoldering eye sockets, canceling his invulnerability glow and freezing him in place. That window is exactly long enough for Taranis to blast his immobilized brother to death.
The bolts are the mechanical key that makes killing a god possible, and their use here resolves Carl's long-unsolvable Emberus problem.
Heavy enchanted crossbow bolts, rare and precious — one of a set of ten.
Katia's god-immobilizing bolts, used by Donut to pin and expose Emberus for the killing blow.
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