In Christian mythology, Armageddon (Greek Αρμαγεδδων; [armageddôn] also spelled Har-Magedon in some modern English translations; also known as Mount of Megiddo), is the site of the final battle (or campaign) between God and Satan (whose name means 'adversary'), also known as the Devil. Satan will operate through the person known as the "Beast" or the Antichrist, written about in the Book of Revelation in the Christian New Testament. More generally, it can also refer to an apocalyptic catastrophe. (Contrast Joel 3:10 with Isaiah 2:4 and Micah 4:3 "They shall beat their swords into ploughshares and their spears into pruning hooks. Nation shall not raise sword against nation nor train for war any more." The Joel quote describes an event, Armageddon, where the Isaiah and Micah quotes describe a condition for the earth after Armageddon.)
The word Armageddon in Scripture is known only from a single verse in the Greek New Testament, where it is said to be Hebrew, and is thought to represent the Hebrew words Har Megido (הר מגידו), meaning "Mountain of Megiddo". Some critics may argue that the word Armageddon is an early example of a mondegreen. Megiddo was the location of many decisive battles in ancient times (see Battle of Megiddo).