Shisagishin

Creatures killed by an shisagishin are difficult to bring back to life or to animate as undead. The shisagishin automatically attempts to counteract any attempt to resurrect or animate as undead any creature that it has killed (counteract modifier +21, counteract level 6th). If the shisagishin who slew the creature is itself slain, the creature can be brought back from death or become undead normally.

Requirements Initiative hasn't yet been rolled, and the shisagishin is disguised as a corpse with Manifest Corpse Shell

The shisagishin violently unfolds into their true form, shredding their decaying corpse shell, and attempts a claw Strike on an adjacent target before they roll initiative.

Trigger A creature within the monster's reach uses a manipulate action or a move action, makes a ranged attack, or leaves a square during a move action it's using. Effect The monster attempts a melee Strike against the triggering creature. If the attack is a critical hit and the trigger was a manipulate action, the monster disrupts that action. This Strike doesn't count toward the monster's multiple attack penalty, and its multiple attack penalty doesn't apply to this Strike.

The shisagishin tucks their arms and legs into their body, drops Prone, and manifests a decaying and/or mutilated humanoid corpse around themself over the course of 10 minutes of concentration. The shisagishin can cause this corpse to appear to be the remains of a specific creature they've seen before by Impersonating that creature with Deception. Once their corpse shell has manifested, until the next time the shisagishin acts, they appear to be a corpse. They have an automatic result of 44 on Deception checks and DCs to pass as a corpse.

The shisagishin's lantern face glows, causing the flesh of any number of creatures Grabbed or Restrained by them to swiftly begin to decay. Each of those creatures must attempt a DC 32 fortitude save. Critical Success The creature is unaffected. Success The creature takes 2d8 void damage. Failure The creature takes 4d8 void damage and is Enfeebled 1. Critical Failure The creature takes 6d8 void damage and is Enfeebled 2

Requirements The monster's last action was a successful Strike that lists Grab in its damage entry, or the monster has a creature Grabbed or Restrained Effect If used after a Strike, the monster attempts to Grapple the creature using the body part it attacked with. This attempt neither applies nor counts toward the creature's multiple attack penalty. The monster can instead use Grab and choose one creature it's grabbing or restraining with an appendage that has Grab to automatically extend that condition to the end of the monster's next turn.