Quagmire
COMPLEX HAZARD 1(1 action) On its initiative, the quagmire pulls each creature within it 1 square toward the center of the quagmire and 1 step further submerged; a creature that is submerged up to its waist becomes submerged up to its neck, and a creature that is submerged up to its neck is pulled under and has to hold its breath to avoid suffocation.
A creature in the quagmire can attempt a DC 17 Athletics check to Swim to either raise itself by 1 step if its submerged to its neck or worse, or to swim out of the quagmire if its submerged up to only its waist. On a critical failure, the creature is pulled down 1 step. A creature that Swims out of the quagmire escapes the hazard and is Prone adjacent to the quagmire. Other creatures can Aid the creature, typically by using a rope or similar tool, or attempt to pull a creature within their reach out with a DC 17 Athletics check, with the same results as if the creature attempted the check.