From Pathfinder #148: Fires of the Haunted City, which isn't enabled.

Lifeleech Crystal Patches

HAZARD 11

Stealth +20 (expert) or Detect Magic to note the presence of necromantic energies suffusing the crystals.

Description Sharp, bloodthirsty crystals make walking through this chamber treacherous.

Disable DC 30 Religion (expert) to utter prayers that quell the crystals' necromantic compulsion to drink blood

AC 31; Fort +24, Ref +12

Hardness 20, HP 80 (BT 40); Immunities precision, critical hits (except bludgeoning, or sonic); Weaknesses sonic 10

Slice Legs

Trigger A creature with blood moves through a patch of lifeleech crystals.

Effect The crystals twist and slash, animating and cutting into the creature as it walks, dealing 5d8 slashing damage. The creature must attempt a DC 28 Reflex saving throw.

Critical Success The creature is unaffected.

Success The creature takes full damage and is Drained 1.

Failure The creature takes double damage and is Drained 2.

Critical Failure As failure, plus the creature's blood causes fresh growth. A new 10-foot-square patch of lifeleech crystals grows in an adjacent space to the current patch of crystals.

Pathfinder #148: Fires of the Haunted CityOGL