Hephaestus' Sigil (Summoning Key)
Forged in the smith-god's own fire, the Hephaestus' Sigil is whispered to call Hephaestus himself up from the forge — a rare find few ever hold.
The rest (what he does with it, and what he leaves behind) is left for those who earn it to discover.
Sigils stack like any other item, and a stack you split in your inventory or your vault now stays split.
There is a second, separate relic for his Uber version: Hephaestus' Unquenched Brand, which goes into the same altar and calls Uber Hephaestus. It isn't a Sigil upgrade and isn't forged from essence. See Uber Bosses.
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