What does Isaiah 21:2 mean?

A harsh vision has been shown to me: The betrayer keeps betraying, the destroyer keeps destroying. Go ahead, Elam, attack! Media, lay siege! I will put an end to all the suffering Babylon has caused. Isaiah 21:2 - Modern Text Bible

(Isaiah sees a vision of relentless betrayal and destruction. Elam and Media are called to attack Babylon, signaling its downfall and the end of its cruelty.)