From Pathfinder Bestiary 3, which isn't enabled.

Pufferfish

CREATURE -1

The pufferfish defends itself by filling its flexible body with air or water to extend a number of spikes that otherwise lie flat against its skin. While normally quite slow and deliberate, the pufferfish can contort its body to gain a sudden burst of speed that can catch predators off guard.

Swimming in vast shoals through open ocean underneath the sparkling sun, lurking deep in the muddy beds of rivers, or schooling in pristine lakes, fish are found nearly anywhere there is water.

Perception +4; low-light vision

Skills Acrobatics +2, Athletics +4

Str +2, Dex +0, Con +2, Int -5, Wis +1, Cha -2

AC 12; Fort +5, Ref +3, Will +2

HP 12

Toxic Body

Anyone who hits a pufferfish with a melee unarmed attack or a non-reach melee weapon must succeed at a DC 13 Reflex save or be pierced by a spine, taking 1 piercing damage and being exposed to pufferfish venom.

Speed swim 15 feet

Melee Bite +6, Damage 1d6+1 piercing plus Pufferfish Venom

Inflating Rush

The pufferfish Swims up to its Speed and then inflates. Each creature within 5-foot emanation of its space at the end of its movement must succeed at a DC 13 Reflex save or take 1 piercing damage and be exposed to pufferfish venom.

Pufferfish Venom (incapacitation, poison)

Saving Throw DC 16 Fortitude

Maximum Duration 24 hours

Stage 1 1d4 poison damage (1 round)

Stage 2 1d4 poison damage and Off-Guard (1 round)

Stage 3 1d4 poison damage and Paralyzed (1 round)

Stage 4 1d4 poison damage and paralyzed for 2d10 hours (1 round)

Pathfinder Bestiary 3OGL