Glasspane Horror (CR 6)

Large Aberration (Shapechanger)
Alignment: Usually lawful neutral
Initiative: +2 (Dex); Senses: tremorsense 60 ft.

AC: 21 (-1 size, +2 Dex, +10 natural), touch 11, flat-footed 19
Hit Dice: 8d8+32 (68 hp); DR: 5/magic
Fort +6, Ref +4, Will +7
Speed: 30 ft.
Space: 10 ft./10 ft.
Base Attack +6; Grapple +14
Attack: Slam +10 melee
Full Attack: 2 slams +10 melee
Damage: Slam 1d8+6, 2 slams 1d8+4
Special Attacks/Actions: Blinding light
Abilities: Str 18, Dex 14, Con 19, Int 11, Wis 13, Cha 10
Special Qualities: immunity to electricity, multiple forms, spectrum immunity, telepathy
Feats: Lightning Reflexes; Power Attack; Weapon Focus (slam)
Skills: Appraise +11 and Hide +9
Advancement: 9-18 HD (Large); 19-28 HD (Huge)
Climate/Terrain: Any
Organization: Solitary
Treasure/Possessions: Standard

Source: Dragon #89
Dragon Compendium Vol. 1

Blinding Light (Su): Once per round as a standard action, the glasspane horror can emit a burst of light that blinds all creatures within a 30-foot spread who fail DC 16 Fortitude saves. This is a Charisma-based save DC that includes a +2 racial bonus. This blindness lasts for 1d4 minutes. The horror can use this ability only when it is in humanoid form.

Multiple Forms (Su): As a standard action once per round, the glasspane horror can shift into one of three different forms.

Glasspane: The horror can assume the shape of a pane of glass that measures 10 feet by io feet by 1 inch. It can take any other shape with a total of 10 cubic feet and a minimum dimension (height, width, depth) of 1 inch. The glasspane horror is utterly inert in this form, and typically it masquerades as a large window within a frame. It cannot move or take any actions other than to shift into a different form. The horror gains a +20 bonus on Hide checks while in this form, and it ignores the standard size penalty on its check. Only the keenest eyes can note the tiny, telling signs of the horror's presence.

Glistening Cloud: In this form, the glasspane horror becomes a whirlwind of fine, metallic sand. It is approximately 10 feet wide in this form and 10 feet tall. It moves along the ground at its normal movement rate, but never provokes attacks of opportunity for movement unless it attempts to trample a creature. While in this form, the horror gains the ability to trample for 2d6+6 damage. As it enters a creature's space, its whirling, stinging dust slices into its foes.

Nonmagical physical attacks against the horror have a 50% chance of failing to do any damage while it is in this form. Magic weapons and spells affect it as normal.

Humanoid: In humanoid form, the glasspane horror appears as a crystalline creature. It gains the full benefits of the abilities and attributes listed in its stat block above.

Spectrum Immunity (Ex): The glasspane horror is immune to all illusion (pattern) spells, spells with the words color or prismatic in their names, and spells with the light subtype.

Telepathy (Su): A glasspane horror communicates via telepathy with a range of 60 feet.

Glasspane horrors prefer to attack from ambush. When hired by a master, it usually insists that it be given an appropriate place to assume its inert form and ready itself to attack intruders. The honor might take a position with a glass case used to store a treasure, a skylight situated above an important item or doorway, and so forth.

Shapechanger Subtype

A shapechanger has the supernatural ability to assume one or more alternate forms. Many magical effects allow some kind of shape shifting, and not every creature that can change shapes has the shapechanger subtype.

Traits: A shapechanger possesses the following traits (unless otherwise noted in a creature's entry).