pf2e.fyi
From Pathfinder Society Intro #2: United in Purpose, which isn't enabled.

Spiked Pit

HAZARD 2
Stealth +10 (trained, or 0 if the trapdoor is disabled or broken)
Description A wooden trapdoor covers a pit that's 10 feet square and 20 feet deep. Sharp spikes line the bottom of the pit.

Disable DC 14 Thievery to remove the trapdoor

AC 15; Fort +5, Ref +5
Hardness 5, HP 30 (BT 15); Immunities critical hits, precision

Pitfall
Trigger A creature walks onto the trapdoor

Effect The triggering creature falls in and takes 10 bludgeoning damage plus 2d6 piercing damage from sharp implements at the bottom of the pit. That creature can use the Grab an Edge reaction to avoid falling.
Reset Creatures can still fall into the trap, but the trapdoor must be reset manually for the trap to become hidden again.
Pathfinder Society Intro #2: United in PurposeOGL