Eww what if an Aboleth (Giant Plankton) Colony lived inside the Anemone and that was what was slowly killing the Githyanki?
Paragon Plankton King Aberration8/Mnk12:
CR 25; Huge Aberration (Aquatic);
HD 8d8+96(Aberration) , 12d8+144(Monk) , +240(Paragon) ; hp 720;
Init +8; Spd 90, Swim 120;
AC:38 (Flatfooted:28 Touch:29);
Atk +53/48/43 x4 (4 tentacles) base melee, +46/41/36 base ranged; +54 (1d6+35, 4 Tentacles);
SD: DR 20/+6, SR 35, fast healing 20, Fire, Acid resist 10
SA: Transformation (Ex) , Enslave (Su) , Psionics (Sp) Hypnotic Pattern 31 At Will Illusory Wall 31 At Will Mirage Arcana 31 At Will Persistent Image 31 At Will Programmed Image 31 At Will Project Image 31 At Will Veil 31 At Will ; SQ: Mucus Cloud (Ex); AL LE;
SV Fort +42, Ref +38, Will +47;
STR 41, DEX 27, CON 35, INT 30, WIS 35, CHA 32.
Feats: Blind-Fight, Combat Reflexes, Deflect Arrows, Dodge, Expertise, Improved Critical: Tentacles, Improved Trip, Improved Unarmed Strike, Large And In Charge, Mobility, Spring Attack, Stunning Fist, Weapon Focus: Tentacles, Whirlwind Attack.
Paragon Plankton King Aberration8/Mnk12:
CR 25; Huge Aberration (Aquatic);
HD 8d8+96(Aberration) , 12d8+144(Monk) , +240(Paragon) ; hp 720;
Init +8; Spd 90, Swim 120;
AC:38 (Flatfooted:28 Touch:29);
Atk +53/48/43 x4 (4 tentacles) base melee, +46/41/36 base ranged; +54 (1d6+35, 4 Tentacles);
SD: DR 20/+6, SR 35, fast healing 20, Fire, Acid resist 10
SA: Transformation (Ex) , Enslave (Su) , Psionics (Sp) Hypnotic Pattern 31 At Will Illusory Wall 31 At Will Mirage Arcana 31 At Will Persistent Image 31 At Will Programmed Image 31 At Will Project Image 31 At Will Veil 31 At Will ; SQ: Mucus Cloud (Ex); AL LE;
SV Fort +42, Ref +38, Will +47;
STR 41, DEX 27, CON 35, INT 30, WIS 35, CHA 32.
Feats: Blind-Fight, Combat Reflexes, Deflect Arrows, Dodge, Expertise, Improved Critical: Tentacles, Improved Trip, Improved Unarmed Strike, Large And In Charge, Mobility, Spring Attack, Stunning Fist, Weapon Focus: Tentacles, Whirlwind Attack.