n large animal aquatic mindless 

Perception +12; darkvision

Skills Acrobatics +15, Athletics +17, Stealth +15

Str +6 Dex +4 Con +6 Int -5 Wis +0 Cha -5

AC  15; Fort +17, Ref +15, Will +1

HP 165; Immunities mental, precision; Weaknesses piercing 5, slashing 5

Speed swim 20 feet

Melee [>] tentacle +18 (agile, reach 20 feet), Damage 2d8+8 bludgeoning plus jellyfish venom

Jellyfish Venom (poison) Saving Throw DC 25 Fortitude; Maximum Duration 6 rounds; Stage 1 2d8 poison damage and clumsy 1 (1 round); Stage 2 3d6 poison damage and clumsy 2 (1 round); Stage 3 2d10 poison damage and paralyzed (1 round)

Squeeze A giant jellyfish can fit into tight spaces as if it were a Medium creature. It can move at its full Speed while Squeezing.

Bestiary 2, page 152.