pf2e.fyi
From Pathfinder #167: Ready? Fight!, which isn't enabled.

Freezing Floor Tiles

COMPLEX HAZARD 16
Stealth +23 +23 (expert) or DC 38 Perception (master) to notice the four sensors
Description Four remote sensors at each corner of the arena cause bursts of freezing magic to erupt from random tiles on the arena and stop creatures in their tracks.

Disable DC 40 Thievery (legendary) or Dispel Magic (6th rank; counteract DC 38) to disable one of the sensors

AC 36; Fort +33, Ref +30
Hardness 20, HP 40 (BT 20); Immunities cold; Weaknesses fire 15

Frigid Floor (cold)
Trigger Hao Jin signals the beginning of the match.

Effect The trap rolls initiative.
Routine (4 actions) The trap loses 1 action per disabled sensor. On each action, the trap causes a random 10-foot-by-10-foot space in the arena to suddenly freeze. Each creature that begins its turn in a frozen space takes 2d6+2 cold damage (DC 40 basic Reflex save). A creature that critically fails its save also becomes Slowed 1 for 1 round; if it was already slowed, the creature instead becomes Immobilized for 1 round. Any amount of fire damage dealt to a slowed or immobilized creature removes the condition. Frozen tiles become unfrozen at the beginning of the trap's next turn.
Pathfinder #167: Ready? Fight!OGL