The Soulbranded, The Skinchangers, Beastkin
It has been known for a rare few to be born as a Soulbranded, gaining the ability to shift their form into that of an unknown creature almost from birth. These rare ones are often called True Soulbranded, and can be either shunned as more beast than man, or exalted as those who are meant to guard the lands, dependant on the location they dwell within.
There are many benefits to becoming or being born as a Soulbranded. Initially it is known to all that a Soulbranded can change their shape, with a varying degree of effort into that of their bonded creature or animal form. This becomes easier or harder depending on how different the animal is from a humanoid form.
Aside from the ability to change shape, it is possible to take on minor traits from their adopted form, such as enhanced senses, again depending on the type of animal bonded to, for example a Wolf Soulbrand would give enhanced senses of smell to the bearer. The ability to understand communication from that particular breed of animal is also part of the territory of becoming a Soulbranded.
Lastly, and one of the hardest yet more beneficial traits of the Soulbranded is that of 'Hybridisation' - the ability to shift a part of their form just a little, becoming neither human nor animal in that part of their form. This can mean extending claws upon their fingers, shifting their legs to allow their humanoid form to move faster, or many other possibilities.