Tumbling Mound (CR 3)

Medium Plant
Alignment: Always Neutral
Initiative: +1 (Dex); Senses: darkvision 60 ft., low-light vision, and Spot +3

AC: 17 (+1 Dex, +6 natural), touch 11, flat-footed 16
Hit Dice: 6d8+12 (39 hp)
Fort +7, Ref +3, Will +2
Speed: 30 ft.
Space: 5 ft./5 ft.
Base Attack +4; Grapple +7
Attack: Slam +7 melee
Full Attack: 2 slams +7 melee
Damage: Slam 2d6+3
Special Attacks/Actions: Blood drain, improved grab, thorns 2d4
Abilities: Str 16, Dex 12, Con 15, Int 5, Wis 11, Cha 6
Special Qualities: plant traits, resistance to fire 10
Feats: Improved Overrun; Power Attack; Track
Skills: Climb +6, Hide +1*, Spot +3, and Survival +3
Advancement: 7-10 HD (Medium); 11-18 HD (Large)
Climate/Terrain: Warm deserts
Organization: Solitary or cluster (5-8)
Treasure/Possessions: 1/10th coins, 50% goods, 50% items

Source: Sandstorm

Blood Drain (Ex): A tumbling mound derives its needed moisture from blood. It deals 1d4 points of Constitution damage to a grappled creature in any round when it begins its turn grappling the victim. Once it has dealt 8 points of Constitution damage, it releases its grip and tumbles away, sated. If the victim dies before the tumbling mound has drained 8 points of Constitution, the tumbling mound releases its victim and goes in search of a new one. A tumbling mound does not need to deal thorn damage to utilize this ability.

Improved Grab (Ex): To use this ability, a tumbling mound must hit a creature of any size with its slam attack. It can then attempt to start a grapple as a free action without provoking attacks of opportunity. If it wins the grapple check, it establishes a hold and inflicts its thorn damage with each subsequent grapple attempt (no matter who initiates the grapple, including a third party coming to the aid of the tumbling mound's victim). It can also begin draining blood once it has grappled a victim.

Thorns (Ex): Any creature that strikes a tumbling mound with a natural weapon takes 2d4 points of piercing damage from sharp thorns that cover the mound's body.

Skills: *Tumbling mounds have a +8 racial bonus on Hide checks in dry undergrowth or dead vegetation.

A tumbling mound attacks by throwing itself at a target, then driving as many thorns as possible into the victim's flesh to latch on. It feeds by sucking the victim's blood through a hollow "feeder" thorn. Tumbling mounds have enough cunning to choose lightly armored foes over those wearing heavier armor.