Wolf Unit

The Wolf Unit are a pack of vicious wolves stationed in Impel Down's Level 5: Freezing Hell.

Appearance
The wolves look like typical wolves, except their strange looking eyes make them look deranged and insane, and they tend to stick out their tongues, which further increases their bloodthirsty appearances.

Personality
The wolves are extremely savage, to the point of hunting other animals in Level 2: Beast Hell, even the bosses of the Level, the Basilisk and the Sphinx.

Abilities and Powers
The wolves are powerful enough to overwhelm even the top savage animals of Level 2. As such, they are reassigned to guard Level 5 criminals, most of whom have a bounty of over 100,000,000. The wolves also seem to be resistant to the bitter cold of Level 5.

The Wolf Unit usually attack in groups, making them even more lethal.

History
Originally assigned to Level 2: Beast Hell of Impel Down, the Wolf Unit were proven to be too savage and bloodthirsty, as they hunted other animals as well. As such, they were reassigned to Level 5.

When Monkey D. Luffy was poisoned by Chief Warden Magellan and imprisoned in Level 5, Mr. 2 Bon Kurei, along with Mr. 3 and Buggy, came down to rescue him, though the latter two fled in terror upon meeting the Wolf Unit. After rescuing Luffy from his cell, Mr. 2 bravely fought off the pack of savage wolves that kept attacking him. He was rescued by a barely conscious Luffy, who released a massive blast of Haki to scare off the wolves (manga only in the anime he knocks them out cold).

The guards of Impel Down found Vice Warden Hannyabal's headdress, which was stolen by Mr. 2 as part of his disguise, torn and bloody, and they assumed the prisoners were eaten by the wolves, or else both Magellan and Hannyabal would both be demoted for this irresponsibility on their behalf.

After Luffy was cured by Emporio Ivankov, the two, along with Inazuma, fought through the Wolf Unit with extreme ease and made it to Level 6: Eternal Hell.