Plant: Monstrous flytraps have the traits and immunities common to plants.
Improved Grab (Ex): To use this ability, a monstrous flytrap must hit with its bite attack. If it gets a hold, it can attempt to swallow its opponent (see below), provided its opponent is at least two size categories smaller than it. See Improved Grab.
Swallow Whole (Ex): A monstrous flytrap can swallow a grabbed opponent two size categories smaller than it by making a successful grapple check. The swallowed creature can attack the flytrap from inside its mouth using claws or a Small or Tiny slashing weapon. The flytrap does not release its opponent until it is slain or its swallowed prey is completely drained of blood (that is, dead). A monstrous flytrap’s mouth can swallow only one opponent at a time and cannot attack while it drains a creature’s blood.
Blood Drain (Ex): A creature swallowed by a monstrous flytrap takes 1d6+13 points of damage every round due to blood loss. For every 3 hit points it drains, the monstrous flytrap heals 1 hit point of damage. After draining its swallowed prey to death, it expectorates the lifeless husk and seeks out its next meal.
Automatic Language: Monstrous flytraps raised from seedlings can be taught to speak (but neither read nor write) one language.
Monstrous Flytrap: CR 7; Huge plant; HD 11d8+55; hp 104; Mas —; Init –2; Spd 20 ft.; Defense 14, touch 6, flat-footed 14 (–2 size, –2 Dex, +8 natural); BAB +8; Grap +25; Atk +16 melee (1d6+13, bite); Full Atk +16/+11 melee (1d6+13, bite), or +5 ranged; FS 15 ft. by 15 ft.; Reach 10 ft.; SQ plant, improved grab, swallow whole, blood drain 1d6+13, blindsight 60 ft.; AL none or owner; SV Fort +12, Ref +1, Will +5; AP 0; Rep +0; Str 28, Dex 7, Con 21, Int 10, Wis 14, Cha 14.
Advancement: 12–16 HD (Huge); 17–32 HD (Gargantuan); 33–48 HD (Colossal).
Advanced Monstrous Flytrap: CR 12; Gargantuan plant; HD 22d8+154; hp 253; Mas —; Init –2; Spd 20 ft.; Defense 16, touch 4, flat-footed 16 (–4 size, –2 Dex, +12 natural); BAB +16; Grap +41; Atk +25 melee (1d8+19, bite); Full Atk +25/_+20/_+15/_+10 melee (1d8+19, bite), or +9 ranged; FS 20 ft. by 20 ft.; Reach 15 ft.; SQ plant, improved grab, swallow whole, blood drain 1d8+19, blindsight 60 ft.; AL none or owner; SV Fort +20, Ref +5, Will +9; AP 0; Rep +0; Str 36, Dex 7, Con 25, Int 10, Wis 14, Cha 14.