cn small amphibious beast 

Perception +9; darkvision

Languages Aquan, Common

Skills Acrobatics +8, Athletics +7 (+9 to Grapple), Medicine +9, Survival +7

Str +3 Dex +4 Con +1 Int +1 Wis +3 Cha +1

AC  18; Fort +7, Ref +10, Will +7

HP 35

Head Bowl The depression atop a kappa's head is filled with water. Spilling, evaporating, or otherwise removing all of the water from the top of a kappa's head reduces all their Speeds to 5 feet until the basin is again filled with water. A kappa who becomes prone must succeed at a DC 15 Reflex save or spill their water, and a kappa who becomes unconscious automatically spills their water. If a kappa is grappled, restrained, or stunned, another creature can attempt to spill the water from their bowl by spending a single action, which has the attack and manipulate traits, to attempt an Athletics check against the kappa's Fortitude DC. On a success, the creature spills the kappa's water.

Speed 15 feet, swim 40 feet

Melee [>] claw +11 (agile), Damage 1d10+3 slashing

Pull Arm [>] The kappa pulls one of their arms, gaining 10-foot reach with that arm. The opposing arm shrinks to little more than a hand extending from their shell. The kappa can still use their shortened hand to hold things, but they can't use that hand to wield a shield or weapon. By spending a single action to pull their opposing arm, the kappa can return their arms to their original length.

Bestiary 3, page 147.