Amazing polymorph forms

[Ravingdork]

What are some amazing polymorph forms that you have used, seen used, or can come up with? I'm hoping to get a small library going of some established form for people to quickly snatch up.

I'll start:

AMORPHOUS FORM (polymorph I)
Your appearance doesn't change, but you become more fluid and insubstantial.
Small humanoid
Speed swim 30 ft.
Melee slam +3 (1d4 B)
Special Abilities compression

AQUATIC FORM (polymorph I)
You suddenly sprout fins and gills.
Medium humanoid
Speed swim 30 ft.
Melee slam +3 (1d4 B)
Special Abilities water breathing

AVIAN FORM (polymorph II)
You transform into a small bird of your choice.
Small animal
Senses low-light vision
Speed 20 ft., fly 30 ft.
Melee bite +6 (1d6 B)
Special Abilities Strix mobility

PISCINE FORM (alert variant, polymorph II)
You take the form of a small deep sea fish with bulging eyes.
Small animal
Senses blindsight (sound) 60 ft., low-light vision
Speed swim 30 ft.
Melee slam +6 (1d6 B)
Special Abilities Kalo vision, water breathing

PISCINE FORM (fast variant, polymorph II)
You turn into a big fish with powerful muscles and fins.
Medium animal
Senses low-light vision
Speed 20 ft., swim 50 ft.
Melee slam +6 (1d6 B)
Special Abilities Kalo movement, water breathing