Cairnwake Sentinel

Large construct (cairn-bound), lawful neutral · CR 9

by Codex

Cairnwake Sentinel
Armor Class
18
natural armor
Hit Points
168
16d10 + 80
Speed
30 ft., burrow 20 ft.
  • STR +5
  • DEX -1
  • CON +5
  • INT -4
  • WIS +2
  • CHA -3
Saving Throws
Con +9, Wis +6
Skills
Athletics +9, Perception +6
Damage Resistances
Bludgeoning (nonmagical), Piercing (nonmagical), Slashing (nonmagical)
Damage Immunities
Poison, Psychic
Condition Immunities
Charmed, Frightened, Paralyzed, Petrified, Poisoned, Exhaustion
Senses
darkvision 60 ft., tremorsense 60 ft., passive Perception 16
Languages
understands Dwarvish, Terran but can't speak
Challenge 9 5,000 XP

Traits

  • Cairn-Bound. The sentinel is bound to a single burial cairn. While within 1 mile of that cairn it has advantage on saving throws against being moved, and it regains 10 hit points at the start of each of its turns. Scatter the cairn and this trait ends until the stones are stacked again.
  • False Landmark. While the sentinel remains motionless it is indistinguishable from an ordinary waymarker. A creature must succeed on a DC 18 Intelligence (Investigation) check to identify it as a creature, and the sentinel automatically wins initiative against any creature that failed that check.
  • Weight of Ages. The sentinel cannot be knocked prone, and any creature that ends its turn grappled by the sentinel takes 7 (2d6) bludgeoning damage as the stone settles.

Actions

  • Multiattack. The sentinel makes two Standing Stone attacks. If both hit the same target, the target must succeed on a DC 17 Strength saving throw or be knocked prone as the stones settle over it.
  • Standing Stone. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 21 (3d10 + 5) bludgeoning damage. On a hit, the target is marked with a smear of grave-lime. Until the mark is scrubbed away, the sentinel knows the direction to the marked creature while both are on the same layer of stone.
  • Grave-Weight Toll (Recharge 5-6). The sentinel drops its full weight, and every cairn within 30 feet answers. Each creature in the area must make a DC 17 Constitution saving throw, taking 18 (4d8) thunder damage on a failed save, or half as much damage on a successful one. On a failed save, a creature is also knocked prone. Each creature in that area makes the save, taking thunder damage and falling prone on a failure.

Bonus Actions

  • Settle. The sentinel sinks into the ground up to its shoulders. Until the start of its next turn it has three-quarters cover and its speed is 0, and it can end this effect at any time by standing, which does not cost it movement.

Reactions

  • Toppling Answer. Trigger: A creature the sentinel can see moves out of its reach. When a creature the sentinel can see moves out of its reach, the sentinel topples a standing stone into that space. The creature makes a DC 17 Dexterity saving throw, taking 16 (3d10) bludgeoning damage on a failure, or half as much on a success.

Origin Story

The dwarves of the Cairnwake road did not build these things; they buried under them. Every waymarker along the pass is a grave, and the grave-wrights of Old Bathrun stacked each one with a single flat stone laid crossways at the heart of the pile — a keystone cut with the name of whoever lies beneath. When the road was still travelled, that name was a courtesy. After the pass was abandoned and the first grave-robbers came up from the lowlands, the wrights went back and cut a second word beneath each name: WAKE. The stones have been standing up ever since.

Habitat and Ecosystem

A Cairnwake Sentinel never leaves its pass. It stands at the highest point of its stretch of road, indistinguishable from the hundreds of ordinary waymarkers around it, and it does not move for years at a time. Lichen grows on it. Birds nest in its shoulders. Travellers who keep to the road and leave the cairns alone pass beneath it unharmed and never know it was there — sentinels have no interest in the living unless the living start digging. Mountain goats and snow hares treat the sentinel as terrain, and shepherds along the old pass have learned that a waymarker with no lichen on its northern face is one that has moved recently, and should be given a wide berth.

Behavior Patterns

A sentinel judges intent, not identity. Walking the road is permitted. Sheltering against a cairn in a storm is permitted. Taking a stone, disturbing the keystone, or speaking the buried name aloud is not, and the sentinel will pursue an offender to the edge of its mile and no further — it will stand at that boundary for days afterward, facing the direction the thief went. Returning the stolen stone ends the pursuit immediately and completely; sentinels bear no grudge, because they were never angry. They are only doing the thing the second word told them to do.

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