Bloodthorn (CR 3)

Large Plant (Extraplanar)
Alignment: Always neutral
Initiative: +3 (Dex); Senses: low-light vision

AC: 16 (-1 size, +3 Dex, +4 natural), touch 12, flat-footed 13
Hit Dice: 3d8+12 (25 hp)
Fort +7, Ref +4, Will -2
Speed: 0 ft.
Space: 10 ft./10 ft.
Base Attack +2; Grapple +11
Attack: Tendril +6 melee
Full Attack: 4 tendrils +6 melee
Damage: Tendril 1d8+5
Special Attacks/Actions: Blood drain, improved grab
Abilities: Str 20, Dex 17, Con 19, Int -, Wis 12, Cha 2
Special Qualities: Plant traits
Advancement: 4-6 HD (Large); 7-15 HD (Huge)
Climate/Terrain: Any desert and plains (Abyss, Carceri, Outlands, Pandemonium)
Organization: Solitary
Treasure/Possessions: -

Source: Fiend Folio

A bloodthorn seems to be a normal plant until a living creature comes within the reach of its tendrils. It then lashes out with as many tendrils as possible and drains the victim of blood. A bloodthorn allows scavengers to remove the carcasses, thus keeping the area around the plant free of its consumed prey

A bloodthorn can be summoned using a summon nature's ally IV spell.

Blood Drain (Ex): If a bloodthorn grabs an opponent, it begins draining blood. It deals 1d4 points of Constitution damage with each successful grapple check. If the opponent wins a grapple check, one of the bloodthorn's tentacles comes loose from the opponent's body. The resulting wound continues to lose blood for 1 additional round.

Improved Grab (Ex): If a bloodthorn hits an opponent that is at least one size category smaller than itself with at least two tendril attacks, it deals normal damage for each tendril and attempts to start a grapple as a free action without provoking an attack of opportunity (grapple bonus +11). If it gets a hold, it can use its blood drain ability. Thereafter, the bloodthorn has the option to conduct the grapple normally, or simply use two tendrils to hold the opponent (-20 penalty on grapple check, but the bloodthorn is not considered grappled). In either case, each successful grapple check it makes during successive rounds automatically deals tendril damage and drains blood.

Extraplanar Subtype

A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.

Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.