Revelation 12:9 identifies the great dragon as that ancient serpent called the devil and what?

Answer: Satan

The great dragon, that ancient serpent called the devil and Satan, the deceiver of the whole world, was hurled to the earth.

“And the great dragon was hurled down—that ancient serpent called the devil and Satan, the deceiver of the whole world. He was hurled to the earth, and his angels with him.”— Revelation 12:9 (BSB)