The Avenger bugs are a series of bugs involving the weapon Avenger in Final Fantasy IV. Several bugs include the following. * Weapon properties and stats don't change when equipping the Avenger in combat (affects all SNES versions) * Equipping the Avenger while in combat doesn't change the previous weapon's stats to the Avenger. The result is effectively like casting Berserk on the character. The previous weapon's attack power and elemental effects are preserved. This bug is only useful to avoid the Crystal Armor's Berserk protection. * Kain 'casts magic' while equipped with the Avenger in Zeromus battle (affects FF2US [both 1.0 and 1.1] and FF4) * When Kain equips the Avenger, there is some strange interaction with the Avenger's reapplying Berserk and the hidden "Black Hole"