pf2e.fyi
From Pathfinder Lost Omens Shining Kingdoms, which isn't enabled.

Guillotine Blade

FEAT 18
ARCHETYPECONCENTRATEOCCULT
Activity 1 action
Archetype Splinter of Finality
Prerequisites Spectral Dagger
Frequency once per day

The echoes of the splinter of finality's original purpose resonate through the artifact. For the next minute, your Spectral Dagger gains the benefits of a Vorpal rune. When you use Snicker-Snack with your spectral dagger, the DC of the Fortitude save is 37, your class DC, or your spell DC, whichever is higher.

Pathfinder Lost Omens Shining KingdomsORC