Beastiary : my own version

Harpies

Harpies, singular Harpy, are a race of  eagle-like shape shifters known for their strong determination and their metallic coloured plumage. They are also known as were-eagles due to being similar creatures to werewolves. Harpies are however often found as rivals to werewolves despite there similarities such as both being social creatures, wolves being found in a Pack while Harpies being found in a Flock.

When a Harpy shifts they gain dilated bird-like pupils covering over their irises along with yellow coloured scleras. They also gain sharp steel-like talons along with powerful wings granting them the ability to fly, these talons and wings always match in colour and can be either bronze, silver or gold. It should be noted however Harpies, like werewolves, can activate different parts of their shift without having to fully transform.

Becoming a Harpy:
Harpies can be either born by having one or both of their parents be a harpy, or turned by having a human scratched by a Harpies talons, if infected the human will either die or become a new born Harpy. This scratch however, similar to werewolves bite, won't effect other supernaturals or humans infused with magic.

Behaviour:
Harpies can be wild creatures and tend to have fierce personalities, they are often very determined, straight to the point, stubborn and sometimes aggressive, they know what they want and take it, not usually affected by distractions, although some may break this stereotype. Harpies tend to be loyal and compassionate towards other members of there Flock, and even weaker, younger Harpies will show bravery and strength to defend one of there own.

Powers and abilities:
Harpies have there own special traits and talents giving them an advantage over humans and other supernaturals.

Flight: Once shifted a Harpy can use their wings to fly great distances however extended amounts of time can be exhausting.
Long ranged vision: Once shifted a Harpies eyes can see things clearly from long distances where humans could not.
Aerial adaptation: Harpies can adapt to the oxygen levels, temperatures and air pressure of the sky allowing them to fly high up into the atmosphere without suffering any ill effects.
Superhuman strength: Harpies are very strong capable of over powering humans and weaker supernaturals.
Superhuman speed: They are able to run, dodge and react quicker than humans capable of exceeding Olympic athletes on foot while able to move faster than cars in flight.
Superhuman endurance: Harpies don't get tired out as much as humans so they can run, fight and do other physical activities without getting tired as quickly,  they can eventually tire but it can take awhile, they can also take more physical damage than humans able to withstand multiple bullets and knife wounds.
Superhuman healing: Harpies can heal from injuries much quicker and better than humans, they are also immune to diseases and becoming a Harpy can cure natural disabilities.
Retractable talons: Harpies have metallic talons that are capable of shredding most materials.
Longevity: Harpies age slower than humans and therefore have an extended lifespan.

Weaknesses:
Despite there fierce nature like all creatures Harpies can be weakened and killed.

Mortality: Even though Harpies can live longer than humans they will eventually die over time and can be killed by mortal weapons however it should be noted that they are more endurant that humans and can heal from a lot of mortal injuries.
Black iris: Iris chrysographes, more commonly known as the black iris, is a plant that is extremely poisonous towards Harpies and can be used to weaken, render unconscious and, if used efficiently, kill a Harpy. In other words Black Iris effects Harpies like wolfsbane effects werewolves.