Nazgûl

Nazgûl are scary bad guys from the book and movie series "The Lord of the Rings". They are humans who had evil thoughts and were tempted by a powerful ring. They became slaves to the ring and to the dark lord who ruled over them.

They wear black robes and ride on big flying beasts called "fellbeasts" that look like scary dragon-birds! When they come around, you know something bad is going to happen!

The Nazgûl are also known as "Ringwraiths". They are scary because they are almost invincible and they can't be killed easily. They can also sense the presence of the ring, which makes them very dangerous. If they find someone with the ring, they will try to take it and bring it back to their dark lord.

So, in short, Nazgûl are scary bad guys who are slaves to the ring and the dark lord. They wear black robes, ride on scary dragon-birds, and are almost invincible. If they find someone with the ring, they will try to take it and bring it back to their dark lord.