Haunted House (CR 18)

This decrepit house’s windows seem like glowing, malevolent eyes, and its front porch a fanged maw. A pair of trees on either side of it grasp at the sky like claws.

CE Colossal undead
Senses: all-around vision, lifesense 80ft
Aura: frightful presence (60ft, DC 30)

==Defense==

AC 33, touch 0, flat-footed 33 (-3 Dex, +34 natural, -8 size)
hp 297 (22d8+198); fast healing 10
Fort +16, Ref +4, Will +22
Immune: construct traits, undead traits
DR 10/adamantine, SR 29
Weaknesses: vulnerable to fire

==Offense==

Speed: 30ft, ground breaker
Melee: 2 claws +28 (4d8+19/19-20 plus 3d6 negative energy), bite +28 (4d10+28/19-20 plus 3d6 negative energy and grab), tongue +26 (grab)
Space 40ft; Reach 30ft (10ft with bite)
Special Attacks: double damage against objects, fast swallow, swallow whole (5d10 negative energy, AC 27, 29 hp), trample (4d10+28, DC 40)
Spell-Like Abilities (CL 18th)
—3/day: Harm

==Statistics==

Str 49, Dex 5, Con —, Int 5, Wis 24, Cha 28
BAB +16, CMB +43 (+45 grapple, bull rush and trip; +47 overrun), CMD 50 (can’t be tripped)
Feats: Weapon Focus (natural), Improved Critical (natural), Iron Will, Awesome Blow, Intimidating Prowess, Powerful Maneuvers, Multiattack, Vital Strike, Improved Vital Strike, Greater Vital Strike, Greater Overrun
SQ: crushing timbers, freeze, haunted

==Ecology==

Environment: Any land
Organization: solitary or household (1 plus 1-10 incorporeal undead)
Treasure: standard

==Special Abilities==

Crushing Timbers (Ex): A haunted house’s bite always deals damage equal to 1-1/2 times its Strength modifier, even though it has other natural attacks.

Ground Breaker (Ex): A haunted house is set into its foundation, and pulls itself through the ground. It ignores difficult terrain, and any square it moves through becomes difficult terrain.

Haunted (Su): Although it began existence as a building, a haunted house’s power is derived from an angry ghost. It is treated as both a construct and an undead creature for effects that target these creatures, and also possesses all the immunities of a construct.

Swallow Whole: Creatures “swallowed” by a haunted house are simply trapped inside, though escaping the house proves difficult. The haunted house’s damage reduction applies to its inside as well. Creatures protected by Death Ward are unharmed by the haunted house’s swallow whole ability, as are creatures that don’t take damage from negative energy.

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While a traditional haunted house might be filled with ghosts, haunts, and other undead, the purest form of this concept occurs when an unquiet spirit is bound to its home. The angry soul permeates the very timbers of the building, and gives it a hateful intelligence.