pf2e.fyi
From Pathfinder Bounty #7: Cleanup Duty, which isn't enabled.

Ancient Ooze Pit

HAZARD 0
Stealth +8
Description A trap door covers a pit that is 10 feet square and 10 feet deep. An acidic mass that was once a gelatinous cube lies at the bottom.

Disable DC 12 Thievery to remove the trapdoor

AC 10; Fort +1, Ref +1
Hardness 3, HP 12 (BT 6); Immunities critical hits, precision

Pitfall
Trigger A creature walks onto the trapdoor

Effect The triggering creature falls in and takes 5 bludgeoning damage as the acidic mass breaks their fall, then 1d6 acid damage as the ooze bursts from the impact. 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. The remains of the burst ooze seep into the ground, and the trap functions as a normal Hidden Pit.
Pathfinder Bounty #7: Cleanup DutyOGL