Mosslord (CR 16)

Large Plant
Alignment: Always chaotic neutral
Initiative: +1 (Dex); Senses: low-light vision, Listen +27, and Spot +27
Languages: Understand Common and Sylvan, telepathy 100 ft.

AC: 29 (-1 size, +1 Dex, +19 natural), touch 10, flat-footed 28
Hit Dice: 20d8+180 (270 hp); DR: 15/magic and slashing
Fort +21, Ref +9, Will +12
Speed: 40 ft.
Space: 10 ft./10 ft.
Base Attack +15; Grapple +30
Attack: Tentacle +25 melee
Full Attack: 6 tentacles +25 melee
Damage: tentacle 2d6+11
Special Attacks/Actions: Brainlance, improved grab, mossy transformation
Abilities: Str 33, Dex 12, Con 28, Int 15, Wis 18, Cha 19
Special Qualities: immune to fire, mental reflection, plant traits
Feats: Combat Expertise; Combat Reflexes; Improved Disarm; Improved Trip; Iron Will; Lightning Reflexes; Stealthy
Skills: Escape Artist +24, Hide +22, Jump +15, Listen +27, Move Silently +3, Spot +27, and Use Rope +1 (+3 bindings)
Advancement: 21-25 HD (Large), 26-35 HD (Huge), 36-40 HD (Gargantuan)
Climate/Terrain: Temperate forests
Organization: Solitary or swath (one mosslord plus 1d4+4 shambling mounds)
Treasure/Possessions: Standard

Source: Web

Brainlance (Su): Once a round, a mosslord can emit a powerful lance of focused psionic energy as a free action. It can target any creature with an Intelligence within 60 feet with this brainlance. The creature targeted must make a successful DC 24 Will saving throw or be stunned for 1d4 rounds and take 1d6 points of Intelligence damage. A successful Will save indicates that the target is dazed for 1 round, after which it can act normally; it is also immune to that particular mosslord's brainlance power for 24 hours. The save DC is Charisma-based.

Improved Grab (Ex): If a mosslord hits an opponent with a tentacle attack, it deals normal damage and attempts to start a grapple as a free action without provoking an attack of opportunity. If it gets a hold, it can use its mossy transformation attack on the creature grappled. Thereafter, the mosslord has the option to conduct the grapple normally, or simply use its tentacle to hold the opponent (-20 penalty on grapple check, but the mosslord is not considered grappled). In either case, each successful grapple check it makes during successive rounds allows it to use its mossy transformation attack.

Mossy Transformation (Su): A non-plant, living creature grappled by a mosslord must make a successful DC 29 Fortitude saving throw each round or suffer 1d6 points of Dexterity drain; the victim must make a separate saving throw for each tentacle currently grappling it. A victim drained to 0 Dexterity collapses inward on itself, turning into an inert heap of dark green moss. Over the course of the next 1d4 rounds, the victim's mossy carcass swells and transforms into a shambling mound. The shambling mound is free-willed, yet regards the mosslord that created it as an ally and does what it can to serve its creator. A victim transformed in this manner is not dead, but it retains no memories, abilities, or skills from its past life. A wish or miracle can restore the victim to its prior form (restoring all drained Dexterity in the process). A break enchantment against DC 30 can also revert the victim to its true form (but its Dexterity score remains at 0 until other magic restores it). The saving throw DC is Constitution-based.

Mental Reflection (Su): A mosslord is a plant, and therefore it is immune to mind-affecting attacks. Worse, its powerful mind can usurp control over mind-affecting attacks that are initiated within the range of its telepathy (a 100-foot radius), no matter where they are aimed. Any creature that uses a mind-affecting attack while in this area has a 50% chance that the attack is reflected back upon him, as if the mosslord itself used the attack against him. If an attack is reflected, the original target of the attack is not affected by the attack. A mosslord always reflects mind-affecting attacks that target it specifically. This power has no effect on the brainlance power of other mosslords. This power also doesn't work against mind-affecting attacks delivered by touch or against effect and area mind-affecting attacks.

A mosslord is remarkably adept at hiding, despite its large size, and it usually lies in wait once it detects a nearby non-plant target. Once it attacks, it fights with great tactical skill, using the surrounding terrain as cover and brainlancing any spellcasters before moving in to crush foes with its tentacles and transform them into something more to its liking.