Bonetree (CR 5)
Alignment: Always neutral
Initiative: +0; Senses: tremorsense 60 ft.
AC: 12 (-2 size, +4 natural), touch 8, flat-footed 12
Hit Dice: 11d8+55 (104 hp)
Fort +12, Ref +3, Will +3
Speed: 0 ft.
Space: 10 ft./10 ft., 30 ft. with stinging vines
Base Attack +8; Grapple +11
Attack: Stinging vines +6 melee
Full Attack: Stinging vines +6 melee
Damage: Stinging vines 1d4 and poison
Special Attacks/Actions: Stinging vines, poison, constitution drain
Abilities: Str 10, Dex 10, Con 20, Int -, Wis 10, Cha 2
Special Qualities: bonegrowth, fire resistance 10, energy flash, plant traits
Advancement: 12-16 HD (Huge); 17-32 HD (Gargantuan); 33+ HD (Colossal)
Climate/Terrain: Warm marsh
Organization: Solitary or grove (2-8)
Treasure/Possessions: 1/10 coins, 50% goods, 50% items
Dragon Compendium Vol. 1
When a bonetree senses prey, it begins to rattle its branches in anticipation. This creates an unnerving sound that resembles a nest of rattlesnakes.
Stinging Vines (Ex): Seconds after a bonetree senses prey, a writhing forest of stinging vines whip out of the numerous holes that dot its trunk. These vines flail about to a range of 30 feet, attacking any creature in range. A bonetree can attack all such creatures in range at the same time, but it can make only one attack roll per target. The bonetree can even attack targets underwater or behind cover (though the AC bonus for the target's cover applies).
Poison (Ex): Anyone struck by the bonetree's stinging vines must make a successful Fortitude save (DC 20). If the saving throw fails, the character takes 1d6 points of temporary Dexterity damage. A second save must be made 1 minute later to avoid 1d6 points of secondary Dexterity damage and paralysis.
Constitution Drain (Ex): Once it has paralyzed a victim, the stinging vines automatically attach to the victim. The vines quickly extrude a nest of tiny filaments that worm their way into the flesh of the victim and begin to exude a horrible enzyme that dissolves bone while leaving surrounding tissues intact. This process drains 1 point of Constitution each round following the round in which the vine latched on to the victim. These feeding filaments are quite fragile and cannot be used against a mobile creature. Removing the filaments from a paralyzed or the otherwise helpless victim requires an opposed Strength check and is a move-equivalent action.
Blindsight (Ex): A bonetree has no visual organs but can ascertain all foes within 120 feet using sound-, scent-, and vibration-detecting organs. Bonetrees can even detect creatures underwater.
Bonegrowth (Ex): Once a bonetree has drained at least 3 points of Constitution from a victim or victims, it can "sweat" a foul-smelling mixture of liquefied bone and enzymes from its body as a free action. This layer of sweat hardens into interlocking bony plates in a single round, raising the bonetree's natural armor bonus from +4 to +8 on the bonetree's next action after it has drained the third point of Constitution.
Once a bonetree has drained 6 points of Constitution, it can grow razor sharp bony spurs out of its stinging vines; the spurs fall off after 10 minutes (at which time the bonetree gathers them up to eat them), but until they do so the bonetree's stinging vines deal 3d4 points damage on a successful hit.
The bony exoskeleton degrades at rate of 1 point of natural armor bonus per hour until it is completely reabsorbed by the tree.
Radioactive Flash (Ex): A bonetree's trunk is charged with energy. When it is struck forcefully, this energy is released in a flash of blinding light. Each time a bonetree is struck for damage, the attacker must make a Fortitude saving throw (DC 15) or be blinded for 1 round. Those standing at least 30 feet away gain a +4 bonus to this saving throw. The flash's maximum range is 60 feet.
Creatures in the vicinity can also avert their gaze from the bonetree to avoid this effect.