This mechanical horror bristles with wires, compartments, and blinking lights up and down its thick stalk-like metallic body, balanced atop six spidery legs and bristling with branching armatures, some with cables and clamps and others tipped with gleaming trocars and pneumatic needlers.

Large construct, unaligned

Armor Class 15 (natural armor)
Hit Points 97 (13d10+26)
Speed 15 ft.

17 (+3) 16 (+3) 14 (+2) 13 (+1) 15 (+2) 4 (-3)

Skills Athletics +9, Medicine +8, Perception +5, Sleight of Hand +6
Tools alchemist’s supplies, thieves’ tools Damage Vulnerabilities lightning
Damage Resistances acid, cold
Damage Immunities fire, poison, psychic
Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned; Senses darkvision 60 ft., passive Perception 15
Languages can understand Common and Vilespeech but cannot speak
Challenge 5 (1,800 XP)

Special Traits

  • Medical Installation. Despite its lack of hands, a dissectrinator can use the following equipment: alchemist’s supplies, healer’s kit, and thieves’ tools. It can store up to 50 pounds of such gear in racks and compartments within its body, replacing them when they are exhausted.
  • Pain Threshold. Any attacks or spells that deal 6 points of damage or less do not deal any damage to the dissectrinator.
  • Restraints. The dissectinator has two sets of restraints which it can use to bind a patient. Once it has grappled a creature, it can make grapple checks (whether to maintain the grapple, pin the creature, or perform other special grapple actions) against that creature as a bonus action.
  • Surgical Assistant. A dissectrinator can use the help action to assist Wisdom (Medicine) checks as well as ability and tool kit checks as part of a chirurgical procedure.


  • Multiattack. The dissectrinator makes two melee attacks or three ranged attacks.
  • Clamp. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 7 (1d8+3) bludgeoning damage. Instead of dealing damage, the dissectrinator can grapple the target (escape DC 14).
  • Trocar. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 16 (2d12+3) piercing or slashing damage. Instead of dealing full damage, the dissectrinator can use a syringe dart instead.
  • Syringe Dart (10). Ranged Weapon Attack: +6 to hit, range 40/100 ft., one target. Hit: 10 (3d4+3) piercing damage, and the target must make a DC 13 Constitution saving throw, falling asleep (as the sleep spell) on a failed save, or taking 4 (1d8) poison damage on a successful one.
  • Cortical Puncture. A dissectrinator can use its trocars to drill into the skull of a restrained or unconscious creature and selectively extract portions of the target’s brain. It must pierce the target’s skull with both trocars (a normal attack) but thereafter can maintain the puncture without needing to attack again as long as the target remains restrained or unconscious. A cortical puncture does not deliver poison but instead reduces the target’s Intelligence, Wisdom, and Charisma by 1 at the end of the dissectrinator’s turn each round. A restrained creature makes a DC 14 Constitution saving throw, negating this ability score reduction on a success. The dissectrinator cannot use its darts while performing a cortical puncture. A greater restoration or more powerful healing magic returns a creature’s reduced ability scores to their normal values.

A dissectrinator is an example of the light and dark sides of chirurgical practice. In principle it is a semisentient mechanical assistant, programmed and equipped to aid a surgeon in medical matters both simple and complex, whether it be treating poisons or injuries, dealing with disease, or dissection. of course in the hands of a demented chirurgeon, the cranial dissectrinator becomes a terrifying instrument of torment capable of reducing the bravest of souls to drooling impotence with soulless and heartless clinical precision.

A dissectrinator is 7 feet tall in total, its core body 3 feet tall, atop a set of legs 2 feet long and with a branching set of limbs and sensors making the upper 2 feet. A dissectrinator weighs 500 pounds.

Mad scientists and chirurgeons are nothing if not busy-the demands of their professions leave little time for leisure or distraction, often leading them to leave their diabolical devices unused for long periods of time while important research is conducted or other experiments concluded. There’s no reason to leave a useful tool to be useless however and when a dissectrinator critically malfunctions or decays beyond reliability, it is often repurposed into a trap to doom foolish trespassers.

Clamping Drills

Mechanical Trap

When a creature or object comes within 10 feet of sensors hidden in the wall, floor, or ceiling, pairs of mechanical arms ending in clamps shoot out from small, concealed trap-doors. An area might include multiple sensors, each rigged to its own set of mechanical clamping arms. The trap-doors hiding them are seamlessly constructed and cleverly hidden with natural stonework, into works of art, and even seemingly random splotches of gore. The DC to spot them is 18. With a successful DC 18 Intelligence (Investigation) check, a character can deduce the presence of the sensors or trap doors from variations in the mortar and stone used to create it, compared to the surrounding area. A creature able to carefully cover the sensors from 10 feet away with a flat object, cloth, or wax and a DC 18 Dexterity (thieves’ tools) check to move slowly prevents them from detecting creatures.

When the trap activates, each pair of mechanical clamping arms connected to the sensor makes a melee attack with advantage (+6 bonus to hit) against a random creature within 10 feet of their trap doors (if there are no targets in the area, the mechanical clamping arms don’t hit anything.) A target that is hit becomes grappled (escape DC 14, AC 15, 18 hit points). Once one mechanical clamping arm has grappled a creature, the other transforms into a vicious, crude drill clearly meant to do nothing but harm, dealing 22 (3d12+3) piercing damage on a successful hit. The mechanical arms continue to attack creatures until 1d4 rounds after the creature ceases to move or they are destroyed.

Section 15: Copyright Notice

Book of True Evil. © 2018 Mike Myler, published under license by Legendary Games.