From Pathfinder Bounty #6: The Road from Otari, which isn't enabled.

Hidden Bog

HAZARD -1

Stealth +4

Description This section of grass-strewn ground hides a pool of sticky mud 10 feet across.

Disable DC 15 Crafting or DC 18 Thievery to create a makeshift plank across the hidden bog; creatures can then traverse the hazard's area without stepping into the mud.

Collapse

Trigger A creatures enters the 10-foot-square area of the hidden bog

Effect The creatures squelches into two feet of sticky mud, ending its move action. The mud imposes a -10 foot penalty to the creature's Speed until it is wiped off (requiring ).

Reset Creatures can still step into the mud after the trap is revealed, but the area containing the mud is obvious.

Pathfinder Bounty #6: The Road from OtariOGL