Final Fantasy VI/Bugs and Glitches

Final Fantasy VI -> Bugs and Glitches

Sketch
Be very careful when using Relm's sketch ability in the U.S. version of the game. If it fails on some enemies an uninitialized pointer will cause a bug and mess with the game data, possibly even corrupting save files. If you're using an emulator it's easy enough to avoid this using savestates, or just save often. Since Relm is not required for any sequence in the game except briefly being in your party when exiting Esper mountain some players like myself choose to not bother using her partially for this reason.

Returning to the World of Balance
Early versions of the cartridges for this game featured a bug by which it was possible to return to the world of balance from the world of ruin. In the walkway above the Opera House, where Ultros pushed off the 4 ton weight there are a number of rats running around the scaffolding. If the party lost to them in the world of ruin they would be returned to the Opera House in the world of balance just as if they had failed to prevent Ultros from dropping the weight. After performing this glitch however, there was no way to return to the world of ruin or reclaim the airship so the game was essentially stuck.

Evade
Due to errors in programming, the Evade stat is totally useless. Magic Evade affects both Evade and Magic Evade. As a result, the Blind status effect has no effect on reducing the accuracy of a physical attack.

Vanish+Doom/X-Zone
This is probably the most well-known and most useful out of any of the bugs in the game. The trick comes in realizing that any creature with the "vanish" status has very poor magic defense and it is affected by virtually all spells, including Doom and X-Zone which offer instant kills. Many powerful enemies including most of the bosses in the game can be instantly killed by casting vanish on them and then casting Doom or X-Zone. Doom only affects one enemy, whereas X-Zone affects all enemies. The Vanish and Doom spells can be learned in the world of balance after finishing the magitek factory. The X-Zone spell can be learned in the world of ruin after fighting Phunbaba for the first time.

The best known use for the trick is just using X-Zone to instantly defeat Wrexsoul in Cyan's Sidequest. In general most bosses can be easily defeated by casting vanish on them then doom or x-zone, although in some cases this may keep you from receiving all the rewards you would otherwise and would rob most of the enjoyment of playing the game.