pf2e.fyi
From Pathfinder #218: Titanbane, which isn't enabled.

Hero Killer

ITEM 9
Usage held in 2 hands
Bulk L

Activate (manipulate)

Crafted from nightshade plants that grow near sites of mythic power, this poison wreaks havoc on those with a mythic calling.

Saving Throw DC 28 Fortitude
Onset 1 round
Maximum Duration 5 rounds
Stage 1 3d6 poison damage and lose 1 Mythic Point (1 round)
Stage 2 4d6 poison and Stupefied 1 (1 round)
Stage 3 6d6 poison damage, Stupefied 2, and lose all Mythic Points (1 round)
Pathfinder #218: TitanbaneORC