Doom bug

The Doom bug is a bug found exclusively in the Japanese SNES version of Final Fantasy IV. If a character is under the Doom status, and the player holds the A button throughout the duration of the countdown, once the timer hits 0, the timer will never go any further, thus the character under Doom will never die. This is especially helpful against the Plague Horror boss, as it never deals direct damage and thus, the player can defeat it without worrying about dying from Doom. This bug was fixed in the English release of the game.