Numerous different types of shapeshifters exist in the Anita Blake: Vampire Hunter universe, including werewolves, wererats, and other flavors of lycanthropes, which is a category that includes persons infected by one or more strains of a lycanthropic virus, either inherited or through contact with another lycanthrope's claws or bodily fluids in their shifted form. All lycanthropes are shapeshifters, but not all shapeshifters are lycanthropes. These other shapeshifters include for example some magical creatures who were never human to begin with but can take a humanoid form, and persons who are able to shapeshift as a result of magic, such as a personal or family curse.
- Main article: Legalities
In the Anitaverse, lycanthropes are barred from certain professions and can in fact still be killed on sight in some states. The status of non-lycanthrope shapeshifters, being far more rare, is less clear. To what extent, if any, human society recognizes the authority of lycanthrope social groups (packs, pards, etc.)—whether criminal acts undertaken at the order of one's alpha might be regarded as actions taken under duress, for instance—is similarly unclear. The legalities also change all the time along the series.
- Main article: Lycanthropy
Lycanthropes are humans inflicted with a supernatural virus which allows them to take on the power and appearance of a specific species of animal. The virus can be caught by being scratched or bitten by a lycanthrope, as well as through bodily fluids. The process is unpredictable, and a victim of a lycanthrope attack might survive a serious wound uninfected, or be turned by even the most slightest scratch. Some strains are easier to catch than others.
There are vaccines against lycanthropy, but in rare cases they can infect the patient instead. There are also inoculations that can be given after a person has already been exposed to lycanthropy, which are based on injecting the person with a different strain of lycanthropy in order to get the different strains to cancel each other out. The inoculations can be effective if given quickly enough following the initial infection. However, if the initial exposure didn't cause an infection after all, the inoculation will definitely do so in turn, so using the inoculations is a calculated risk. In extremel rare cases the person might even catch both strains of lycanthropy and become a panwere.
An infected individual will transform for the first time at the next full moon. After that it appears that though full moon triggers an involuntary change, lycanthropes can chose to switch forms at will the rest of the time. The transformation can be extremely painful, as bones and flesh reshape, although not fighting the transformation makes it easier.
Most lycanthropes have two forms, human and animal. However, the strongest lycanthropes are also able to take the form of a hybrid man-beast.
Panweres carry more than one strain of lycanthropy in their blood.
The first true panwere we see in the Anitaverse is Chimera, who is capable of transforming into a werelion, wereleopard, werehyena, wereanaconda, werewolf, and werebear when we first meet him. There is also a possibility that he obtains werecobra infection as well, but he doesn't live long enough to see the following moon when the powers would manifest.
Anita was also believed to be a panwere by Chimera because he sensed that she was part leopard and wolf. Since the Harlequin, Anita is shown to have five beasts residing inside of her. Leopard, wolf, lioness, tiger, and an as of yet undefined animal. It's still unclear what that fifth beast originally was, but later her golden tiger is joined by white, black, red, and blue tigers, and she catches hyena strain from a bullet that goes through Ares and into her. Although she does not shift she comes close a few times and her animals can appear in spirit form when she is in danger.
Some humans are born with the ability to shapeshift. This ability is generally not affected or governed by the full moon, except in the case of inherited lycanthropy. Some of the groups of inherited shapeshifters are:
Witches could potentially shape-shift, with the proper spell and with the skin from a wereanimal. Shifting this way has benefits since the person gains all the power of the skin but is not forced to change with a full moon. Unfortunately, for the spell to work properly, the wereanimal has to die at the end of the spell.
A witch was also responsible for Kaspar Gunderson's ability to shift into a swan. She cast a spell on him, hoping it would make him more compassionate, but that was not to be.
A Lamia is a half human, half snake. They were presumed to be extinct for the past two centuries, but at least one still survives. When we meet Melanie she is Mr. Oliver's servant, but when he dies she begins working at the Circus of the Damned.
Lamias are believed to be "true immortals", as Anita Blake tried and failed to kill her. They can change from human to a half snake form (snake tail/human torso). They have retractable fangs that can inject a lethal poison. Their fangs also inject a substance that can change a human into a Lamia, which was what she was trying to do to her harem in Circus of the Damned.
A naga is a snake-like Hindu creature that is immortal. In The Lunatic Cafe one naga, Mr. Javad, survives being skinned alive by someone who wants the skin for a shapeshifting spell. However, that plan is foiled since nagas are immortal, and the spell requires the original occupant of the skin to be dead by the end of the spell.
Nagas are known as the guardians of pearls and raindrops, in Hindu legend. Their skin has a pearl on the forehead. They are usually shown as cobras/snakes, or human-headed snakes, but can take on a full human form.