The Devil

And I saw an angel come down from heaven, having the key of the bottomless pit and a great chain in his hand. (Revelation 20:1)

And he laid hold on the dragon, that old serpent, which is the Devil, and Satan, and bound him a thousand years, (Revelation 20:2)

And cast him into the bottomless pit, and shut him up, and set a seal upon him, that he should deceive the nations no more, till the thousand years should be fulfilled, and after that he must be loosed a little season. (Revelation 20:3)