History Main / EventFlag

** The last flag that can lock you out of the PacifistRun GoldenEnding occurs slightly ''before'' the flag that disables the last remaining RandomEncounters. This means that, if you time it right, you can engage in a bit of ScriptBreaking and get the "pacifist" ending after killing monsters in the CORE, or even ''wiping them out entirely''.

* ''Franchise/{{Metroid}}''

** The VideoGame/MetroidPrimeTrilogy [[EnforcedTrope Enforces]] this starting with later releases of [[VideoGame/MetroidPrime the first game]], whose updates included measures to prevent SequenceBreaking.

** ''VideoGame/{{Fallout 3}}'' upgraded that engine with a more sophisticated AI system, allowing for more flexible scheduling, conditionals and parameters. There's now quadruple redundancy possible, with event flags set by triggers, spell effects, dialog or AI. A dialog can set an AI flag, which will execute and set a Global variable, which will be checked when a door or object is triggered or a spell times out...and many other possible permutations and chained event flags. Unfortunately, this inconsistency makes it easier to break and harder to debug the chain, which a study of the game in the Construction Set shows many designers have done...

* In ''{{VideoGame/Terraria}}'' boss fights and some other events happen using these flags. Examples include:

* In ''Manga/DailyLifeWithMonsterGirl'', when Kimihito tries to prove [[spoiler:he isn't going to die]], he starts spouting off Death Flags ranging from the oldest ones in the book to {{Shout Out}}s. This is lampshaded by [[SnakePeople Miia]], who urges him to stop saying Death Flags for fear of TemptingFate.

* Referenced in the BeachEpisode of ''LightNovel/HaiyoreNyarkoSan'', where [[UnluckyEverydude Mahiro]] tries to cheer [[FieryRedhead Cuko]] up following the depressing events of the previous episode[[note]]Wherein she had to destroy the next-gen gaming console of her dreams[[/note]]. Cuko thanks him, but says that he's wasting his time if he thinks he can raise any romance flags with her; Mahiro responds "Don't worry, if any flags like that pop up I'll tear them down myself."

* The first ''[[VideoGame/{{Rayman1995}} Rayman]]'' game plays with the concept a little. First of all, event flags only affect the level in which you are. Secondly, the event that sets the flag is just getting into some area; this may mean anything from collecting a powerup through walking a platform up to leap of faith. Moreover, the effects of flag being set are sometimes visible immediately - the game is not above spawning enemies just behind you, and edutainment spinoffs spawn killing obstacles directly into you when you select a wrong answer - but sometimes the only thing you get to know is that you set a flag, due to a distinctive sound - that is, if you play with sound.

** Similarly averted in the sequel, ''VideoGame/{{Riven}}''. The code to the telescope is generated randomly every game this time. However, it's set at the start of the game and there's no actual event flag associated with the events where you learn the code, so there's nothing stopping you from creating a separate save for the game at the start, playing until you learn the code, then reloading that save and inputting the code prematurely. Alternately, if you're really, really bored, you could just sit there and try all 3000+ possible combinations until you brute-force it. [[DevelopersForesights The developers]] [[MultipleEndings accounted for this]] SequenceBreaking.

** In ''[[VideoGame/Metroid2ReturnOfSamus Return of Samus]]'' you have to clear a section of the game world of Metroids before the path forward is cleared of purple liquid, allowing you to advance. ''[[VideoGame/MetroidSamusReturns Samus Returns]]'' changes this to collecting Metroid DNA that is automatically collected from among the drops during the Metroid's death scene.

** Casting Warp ''immediately'' after regaining control after defeating Golbez allows you to walk up and "take" the crystal, which triggers the same event flag as taking the next crystal. With this event flag triggered the Sealed Cave completed event will happen the second you enter, letting you completely avoid one of the game's more annoying dungeons and the [[GoddamnedBoss infernal Trap Doors]] that are found throughout.

* Gen V of ''Franchise/{{Pokemon}}'' makes use of these in an attempt to prevent cheating. It's why using a VideoGame/GameShark for things like a Liberty Pass to get Victini will give you the item, but you can't use it. You have to trigger the Wondercard first. Getting the item from Wi-Fi or the Entrelink triggers the Wondercard which will allow the associated event to occur. The EventFlags exist in all the games, but sharking is easier in earlier gens because just getting the item triggers the flag. There's no Wondercard to trigger when getting the item.

* Franchise/{{Metroid}}

* [[VideoGame/{{Rayman1995}} The first Rayman game]] plays with the concept a little. First of all, event flags only affect the level in which you are. Secondly, the event that sets the flag is just getting into some area; this may mean anything from collecting a powerup through walking a platform up to leap of faith. Moreover, the effects of flag being set are sometimes visible immediately - the game is not above spawning enemies just behind you, and edutainment spinoffs spawn killing obstacles directly into you when you select a wrong answer - but sometimes the only thing you get to know is that you set a flag, due to a distinctive sound - that is, if you play with sound.

** VideoGame/RuneFactory4 continues this spartan tradition by having {{NPC}}s greet you in a way that acknowledges you are in a relationship and/or expecting a child, then following it up with, "...so have you found anyone special yet?" A few other wallbangers include Dylas asking Frey if she will be his friend when she's his wife and the mother of his child, characters commenting that you're dating Dylas if you trigger the "Smiling Practice" event after tying the knot with another bachelor, and Leon continuing to refer to Frey as his girlfriend even after putting a ring on her finger.

* ''Omerta: City of Gangsters'' uses event flags to LevelUp your gangsters. Usually, these happen after a significant battle between your gang and the enemy you're fighting. The stages of the game tell you beforehand if a Level Up event flag is coming.

* [[ClosetGeek Makise Kurisu]] in ''VisualNovel/SteinsGate'' mentions a love flag to Okabe as he gets close to another girl. But [[{Tsundere} tellingly]] she'll only mention this if you've raised the flags for the TrueEnding, which also serves as ''her'' ending.

* ''VideoGame/Persona3'' has a lot of these in regards to the Social Links the player can form throughout the game. One example is that you can't start the Hermit link until you get the copy of "Innocent Sin online" from Junpei.

* In ''VideoGame/SuperMetroid'', the large crashed ship is supposed to be entered from the west; a boss fight there triggers an event flag which turns the power on. Through heavy-duty SequenceBreaking, it can also be entered from the east, but it will be completely empty until this flag is triggered.

** By abusing tents and saving it's possible to walk past Myst and enter from the right, allowing you to skip the destruction of the town and actually explore it much earlier than usual. The shop there sells mid-game items that can be equipped by Rydia, giving the level 1 Summoner twice the raw attack power of the level 10 Cecil and turning her into a [[CrutchCharacter walking]] [[MasterOfAll nuclear]] [[DiskOneNuke bomb]] for much of the game.

-->-- ''VideoGame/CaveStory''s entry for this trope

* Partway through ''VideoGame/TheLegendOfZeldaTheWindWaker'', you're asked to provide a password to get back inside Tetra's pirate ship. However, even if you solve the password riddle perfectly, capital letters and all, the game still won't let you into the ship until you view the correct cutscene where Link overhears the password from two pirates (thus triggering the event flag).

Generally, a BrokenBridge is "repaired" by an event flag, and an unsolvable puzzle [[EnterSolutionHere gets its solution from it]] as well.

Event flags are also how a game knows when YouShouldntKnowThisAlready.

The term is often used for gags in Anime and Japanese games, where GenreSavvy characters talk about needing to [[InvokedTrope set off flags]] for [[BreakingTheFourthWall the plot]] or [[DatingSim relationships]] to move in a [[EarnYourHappyEnding favored direction]]. More commonly, it is a joke about TemptingFate, where once a certain event has been set off, [[{{Troperrific}} something inevitable]] will follow.[[note]]In this situation, when going through said playthroughs, it is a MemeticMutation in the Japanese community.[[/note]] Anybody who talks about [[{{Retirony}} what they're going to do after a war]], for example, has [[DeadManWalking set a death flag]].

* Justified in ''VideoGame/PaperMarioTheThousandYearDoor'' when you have to learn [[spoiler:Doopliss's]] name, which serves as his weakness. Unfortunately for anyone who already knows the name, you also need the ''lowercase letter P from his hideout'' to use in the name entry screen to fill it out properly. And in case you haven't noticed, in the previous appearances of the Name Entry screen, yes, [[DevelopersForesight you have been missing that one single letter since the beginning of the game]].