The Bypass Event Glitch is a bug that can be used to bypass certain scripted events.
Final Fantasy IVEdit
While moving on the world map in the SNES version of Final Fantasy IV, if the player presses the  very quickly, the player can enter the menu while the character is mid-transition. If the player then uses a Tent, the game's collision detection is off by a tile by the time normal gameplay resumes. With this glitch it is possible to avoid visiting the town of Mist when Cecil and Kain are meant to deliver a package there at the beginning of the game. By skipping Mist Kain does not leave the party and Cecil never meets Rydia.
If the player continues to the desert town of Kaipo where Cecil is supposed to go with Rydia's unconscious body, the event where Cecil takes Rydia to the inn still happens with Rydia appearing out of nowhere. During the night soldiers enter the town and Cecil fends them off, only now Kain is also in the party. If the player returns to Mist, they can find Rydia's mother lying on the ground motionless, but there is nothing they can do with her, as the Mist event does not trigger when entering the town from the right side. Mist's weapon shop is open and sells advanced weapons the player is not meant to obtain yet. If the player exists Mist and re-enters from the left side, the event where Mist is burned down by Cecil and Kain's package triggers, but Rydia is already in the party, leading to a battle where Rydia effectively fights herself.
If the player never triggers the event in Mist, but heads for the Underground Waterway to find the cure for Rosa, Tellah, who is supposed to meet Cecil and Rydia in the cave, is not there and never joins the party, but will still appear in cutscenes. After the party makes their way to Damcyan Tellah is meant to battle Edward, but when the game tries to load the battle it freezes.
If the player uses the bypass glitch to bypass the event where the Red Wings attack Damcyan (by offsetting the game's collision detection by a tile and walking through the mountains), Damcyan appears normal on the world map, but is still in a ruined state if the player enters it and it goes on to trigger the scene with Tellah and Edward, freezing the game.
Final Fantasy VIEdit
The bug is activated by opening the main menu and pressing forward (or the direction the player wants to go); this results in bypassing solid "obstacles" that one isn't normally able to pass, including tiles which would trigger events when walked over. Another way to bypass events is to use hacks.
Using a Game Genie and the "Super Sprint Shoes" code, it's possible to bypass the battle with Vargas when the party meets Sabin by reaching the cave entrance before Vargas hops down. The player continues to the Returner Hideout and Sabin will not appear until the Lete River sequence at which point he's suddenly added into the party at level 1, with no equipment and no Blitz abilities.
The South Figaro Glitch, also known as the Moghan glitch, or the Kutan glitch, is the most famous instance of this glitch in the game. This glitch can cause a number of undesirable effects, the most notable being Celes being replaced by the Moogle Moghan, one of the ten moogles from earlier in the game when Locke protected Terra.
The glitch can be activated in Locke's scenario in South Figaro. The player must follow the soldier until he reaches the end of his path. The player should leave one tile in between Locke and the soldier and wait until the soldier is about to move down towards Locke, then open and close the menu quickly and move forward. If done correctly, Locke and the soldier will be standing on the same tile allowing Locke to bypass the soldier on the right side of the town and exit without meeting Celes. Locke will have to go through the Figaro Cave solo, but during the Narshe battle sequence, Celes's slot will be filled in by Moghan. During the Opera House scene, Moghan is unequipped and given Celes's sprite afterward. Moghan is a worthless party unit, unable to equip espers or other equipment, and has low stats, with no unique skills.
The reason for this glitch is that the ten moogles are place-holders for most of the main playable characters; Moghan shares Celes's slot. The moogles are replaced by the true characters once the player has the opportunity to meet and name the playable characters; since skipping Celes in South Figaro means the player never met her, she cannot replace Moghan.
In addition, using this glitch allows Locke to retain one of his alternate costumes from this scenario; while certain cutscenes may show him with his regular sprite, he can remain a green imperial cadet or a merchant for the rest of the game. It is actually possible to keep these costumes while still getting Celes by simply seeing the scene in the basement where Celes is introduced, then leaving South Figaro without rescuing her. In fact, it is possible to turn Moghan into Celes after the scenario by returning to South Figaro and seeing this scene, which will still play even after the scenario is completed.
As a practical purpose, the player can skip sneaking about town in disguise using this glitch - the secret passage out of town will still open for Locke, so once the soldier is bypassed, the player can go through the passage backwards to the basement and rescue Celes, then go back out and proceed through the scenario normally.
If the player skips town like this, later in the game after South Figaro has been liberated, returning to the town will allow them to encounter a leftover merchant in the basement of the pub. The merchant will attack as he would during the scenario, and Locke can still steal his clothing and changes his sprite appropriately. The player can remove the merchant outfit by going through the basement to the spot where they are prompted to remove Locke's disguise or not, but the merchant will not respawn.
The same effect can also be triggered by using the Airship Glitch to skip Locke's scenario. Depending on when this glitch is performed, other characters will also be replaced by Moogles, such as Edgar (replaced by Moggie), Cyan (Moglin), Sabin (Molulu) and Gau (Mugmug). Unlike most bugs, this glitch was not fixed in the Advance re-release.
To bypass the soldier in Magitek Armor on the left side or south side of the town, the player must stand before him and open the main menu. Before closing the menu, they should press in the direction of the obstacle and Leo will pass over the soldier. Unfortunately, the Thamasa map is a slightly different map from the regular Thamasa map, and doesn't have any exits, so Leo cannot leave this map. Even so, this allows the player to skip the Guardian event; however, if Leo tries to leave Thamasa normally, the event will still trigger.
As with the previous methods, the player should stand before the Kaiser Dragon and go into the main menu while having Auto-Dash or the Sprint Shoes on. Holding the  button while exiting out of the main menu will cause the party to bypass the Kaiser Dragon without fighting it.
Final Fantasy VIIEdit
The player can skip the events of returning to Midgar in Part II, and thus avoid many boss battles. However, as the skipped locations are unrevisitable, doing the glitch will have the player miss out on many good treasures. Usually during cutscenes all movement is prohibited, but there are some exceptions where, if the player presses the movement buttons during the scenes, the game considers the player to be moving to a new location, and starts another scene, letting the player skip various areas.
A similar glitch to the Midgar skip, though smaller in scale, can be performed in Junon, where the player can skip some FMVs and other story scenes.