Poliwhirl

Poliwhirl (Japanese: ニョロゾ Nyorozo) is a -type Pokémon introduced in Generation I.

Physiology
Poliwhirl is a large, amphibious froglet-like Pokémon. Poliwhirl has large hands and the hands appear to be like gloves. When a Poliwag evolves, the spiral on its belly reverses direction.

Special abilities
Poliwhirl can have the abilities Damp and Water Absorb. Water Absorb allows Poliwhirl to recover 1/4 of the HP the attack would perform if the attack is a -type. Damp prevents opponents self-destruction. It is capable of living in or out of water; in order to live out of water, it must sweat to keep itself slimy. It prefers to live underwater in ponds where there is less danger. In battle, it uses the spiral shape on its belly to put the foe to sleep. It does this by subtly undulating the spiral, causing drowsiness and eventually sleep. It is also capably of easily escaping the grasp of foes due to its greasy skin.

Evolution
Poliwhirl is the evolved form of Poliwag, as of level 25. Poliwhirl has two choices of evolution - it can evolve into a Poliwrath via a Water Stone, or it can be evolved into a Politoed by trading it with the King's Rock item attached.

Leveling
Generation VI=

Generation V=

Generation IV=

Generation III=

Generation II=

Generation I=

In the TCG
Poliwhirl appears several times in the Pokémon Trading Card Game. More specifically, it appears in the Base Set, Base Set 2, Gym Heroes (as Misty's Poliwhirl), Neo Discovery, Expedition, Skyridge, EX Fire Red & Leaf Green and EX Unseen Forces.

Manga
Red starts his journey with a Poliwhirl and a Bulbasaur, the former being his friend for a long time, and had evolved into Poliwhirl from Poliwag to save him from drowning. It later evolves into Poliwrath to save Red from drowning a second time. Poliwhirl was the only Pokémon of Red's that fought against Lt. Surge to free all of the captured Pokémon.

Trivia

 * The spiral on its belly changes direction after evolving from Poliwag.
 * Poliwhirl is Satoshi Tajiri's (creator of Pokémon) favorite Pokémon.
 * Poliwhirl's Japanese name, Nyorozo, was the name that Satoshi Tajiri had given to his tadpole he found.
 * The spiral on its stomach is based on of a real tadpole. A tadpole's skin would be see-through, thus allowing someone to see the inner intestines.