Vine Horror (CR 4)

Medium Plant (Aquatic)
Alignment: Always neutral evil
Initiative: +0; Senses: Listen +3 and Spot +3

AC: 18 (+8 natural), touch 10, flat-footed 18
Hit Dice: 5d8+20 (42 hp); DR: 5/bludgeoning
Fort +8, Ref +1, Will +2
Speed: 30 ft., swim 20 ft.
Space: 5 ft./5 ft.
Base Attack +3; Grapple +7
Attack: Slam +7 melee
Full Attack: 2 slams +7 melee
Damage: Slam 1d6+4
Special Attacks/Actions: Animate vines
Abilities: Str 18, Dex 10, Con 19, Int 9, Wis 13, Cha 10
Special Qualities: Half damage from piercing and slashing, malleability, plant traits
Feats: Alertness; Blind-fight
Skills: Hide +15*, Listen +3, Spot +3, and Swim +16
Advancement: 6-7 HD (Large); 8-16 HD (Huge)
Climate/Terrain: Any swamp or aquatic
Organization: Solitary or colony (2-12)
Treasure: -

Source: Fiend Folio

Primitive, cruel, and elusive, vine horrors are sentient colonies of algae with the ability to assume a roughly humanoid form. They stalk swamps and similar areas, and they attack by surprise whenever possible.

Vine horrors are often mistaken for green-skinned humanoids with coarse, rough features. A vine horror's features appear smooth and somewhat unformed, and when it speaks, its voice often changes pitch in unusual and seemingly random patterns.

Guided by their own malicious instincts, vine horrors seek to harm and slay any who enter their territory. Communities located too close to swamps or other vine horror lairs often suffer nocturnal attacks by animated trees.

Vine horrors speak Sylvan.

Aquatic Subtype

Creatures with the aquatic subtype always have swim speeds and thus can move in water without making Swim checks. An aquatic creature can breathe underwater. It cannot also breathe air unless it has the amphibious special quality.