Skeksis

The Skekses are an evil race of aliens from Pooh's Adventures of the Dark Crystal who wanted to remain the immortal rulers of Thra. They were eventually destroyed and reverted back into their original UrSkek forms along with the wise and kind Uru who the skekses had opposed. Based on the bonus ending from the film, it can be surmised that the Inner Circle led by Maleficent had aided the skekses in the past, but had now relegated themselves as critics to their evil plan.