History Main / AlgorithmicStoryBranching

* ''VideoGame/EpicBattleFantasy5'': As explained in-depth [[https://epicbattlefantasy.fandom.com/wiki/Endings here]], the ModularEpilogue's scenes are initially determined by which of and whether the RelationshipValues between each possible pair of human {{Player Character}}s has reached certain numbers, with target values determined by number of completed achievements in its AchievementSystem, among other factors. However, it will be the GoldenEnding if the achievement for beating the FinalBoss on the HarderThanHard "Epic" difficulty has been acquired, in any game, or if the party is an {{invoked}} SoloCharacterRun or two-person party ChallengeRun.

[[folder:RPG -- Strategy]]
* ''Franchise/FireEmblem'':
** In ''VideoGame/FireEmblemTheBindingBlade'', whether the fourth act of the story takes place in Ilia or Sacae depends on whether the combined total levels of the players' Pegasus Knights or Nomads is higher, respectively.
** ''VideoGame/FireEmblemTheBlazingBlade'' has several branching chapters that follow a similar system, one is based on whether the Lords' combined levels are above or below 50, the other is the level gains of Hero's Crest-promoting classes vs Guiding Ring-promoting classes.
** ''VideoGame/FireEmblemAwakening'': Most characters don't get married unless the player selects the unlocked S support conversation scene. However, at the end of the first half of the game, there is a cutscene in which Chrom proposes to the unmarried love interest he has the highest [[RelationshipValues Support level]] with. Support points[[note]]gained by fighting next to each other or casting spells on or Dancing for the other[[/note]] count regardless of whether the player has viewed the support conversations they unlock, as there's no chance to view Chrom's supports with Olivia before this point, but she's still a viable option. If he has no support points with any free option, he'll instead get married to a generic village maiden NPC.
** ''VideoGame/FireEmblemThreeHouses'': Unlike in some previous games of the series, only the PlayerCharacter Byleth can reach an [[RelationshipValues S-rank support]] with an NPC, while recruitable [=NPCs=] are restricted to, at most, A-level supports with each other. However, after two recruits achieve an A-level support, the game secretly keeps counting how many times they've assisted each other in combat, and in the ModularEpilogue of the game, all surviving [=NPCs=] are paired off based on this hidden support score, with each receiving a special "paired ending" slide with the person they assisted or were assisted by the most.
* ''VideoGame/TriangleStrategy'': The Scales of Conviction subsystem branches your story (e.g. [[PlayerCharacter Lord Serenoa's]] decision to [[spoiler:surrender or to defend Prince Roland]] in Chapter VII) based on a simple majority vote among his main seven PlayerParty allies, rather than the player directly choosing one branch or the other. Each party member has a preferred branch, but Serenoa can attempt to persuade some of them via dialogue to change their vote [[note]]though whether his persuasion attempt has been successful is not revealed until the vote actually takes place[[/note]], with his own (i.e. the player's) vote serving as a tie-breaker in an even split.
[[/folder]]

Subtrope of StoryBranching. Supertrope to AlignmentBasedEndings -- at least, to the variation where the ending choice is based on the final KarmaMeter standing, rather than a LastSecondEndingChoice. RelationshipValues can also be used as input values for this approach.

* ''VideoGame/TriangleStrategy'': The Scales of Conviction subsystem branches your story (e.g. [[PlayerCharacter Lord Serenoa's]] decision to [[spoiler:surrender or to defend Prince Roland]] in chapter 7) based on a simple majority vote among all recruited and alive PlayerParty members (which characters join your army itself depends on an invisible three-point[[note]]Utility vs. Morality vs. Liberty[[/note]] KarmaMeter). Each party member has a preferred branch, but Serenoa can attempt to persuade some of them via dialogue to change their vote [[note]]though whether his persuasion attempt has been successful is not revealed until the vote actually takes place[[/note]], with his own (i.e. the player's) vote serving as a tie-breaker in an even split.

* ''VideoGame/EpicBattleFantasy5'': As explained in-depth [[https://epicbattlefantasy.fandom.com/wiki/Endings here]], the ModularEpilogue's scenes are initially determined by which of and whether the RelationshipValues between each possible pair of human {{Player Character}}s has reached certain numbers, with target values determined by number of completed achievements in its AchievementSystem, among other factors, but it will be the GoldenEnding if the achievement for beating the FinalBoss is beaten on the HarderThanHard "Epic" difficulty has been acquired, in any game, or if the party is an {{invoked}} SoloCharacterRun or two-person party ChallengeRun.

* ''VideoGame/Cyberpunk2077'': The long-term outcome of the "Sinnerman" sidequest arc depends on multiple dialogues between V and Joshua during said arc, with some choices adding one or two points to Joshua's hidden "doubt" meter. If this meter reaches or exceeds 4 by the end of the questline, [[spoiler:the braindance of his voluntary crucifixion a commercial flop; otherwise, his faith makes it a smash hit]].

* ''VideoGame/ProjectTriangleStrategy'': The Scale of Fate subsystem branches your story (e.g. [[PlayerCharacter Lord Serenoa's]] decision to [[spoiler:surrender or to defend Prince Roland]] in chapter 7) based on a simple majority vote among all recruited and alive PlayerParty members (which characters join your army itself depends on an invisible three-point[[note]]Utility vs. Morality vs. Liberty[[/note]] KarmaMeter). Each party member has a preferred branch, but Serenoa can attempt to persuade some of them via dialogue to change their vote [[note]]though whether his persuasion attempt has been successful is not revealed until the vote actually takes place[[/note]], with his own (i.e. the player's) vote serving as a tie-breaker in an even split.

* ''VideoGame/DragonAgeInquisition'': At the start of the game, the current [[HighPriest Divine]] of the [[TheChurch Chantry]] dies, and towards the end, three high-ranking members of the Inquisition announce their claims as her successors. As explained in-depth [[https://dragonage.fandom.com/wiki/Divine_election here]], each candidate has a hidden score (independent of the regular RelationshipValues) that starts out at 0 at the beginning of the game and goes up or down by anywhere from 1 to 10 points any time the PlayerCharacter makes a decision that directly or indirectly supports her future claim and preferred policies. The candidate with the most points at the end of the game is ultimately elected the next Divine in the epilogue, with a priority list reflecting her respective political clout used to break ties (from the most politically savvy to the least: [[spoiler:Vivienne, Leliana, Cassandra]]).

* ''VideoGame/Cyberpunk2077'': The long-term outcome of the "Sinnerman" sidequest arc depends on multiple dialogues between V and Joshua during said dialogues, with some choices adding one or two points to a hidden meter. If the meter reaches or exceeds 4 by the end of the storyline, Joshua is overcome with doubt and [[spoiler:the braindance of his voluntary crucifixion a commercial flop, otherwise, his faith makes it a smash hit]].

This trope is about an alternative approach that uses numbers and simple arithmetic rules instead of Boolean expressions to control story branching, whereby each decision made by the player increases or decreases one or more (often hidden) numerical scores. Then, when the time comes for the plot to branch, the game checks these scores and selects a branch based either on whether some value is in a specific, writer-defined range, or on which score is the highest at that point. This approach gives narrative designers a lot of expressive power by letting them add new meaningful player choices without having to explicitly account for every possible combination. Another benefit is that choices can now be ''weighted'', with some being assigned larger numeric modifiers than others, thus having a larger, but not dominant effect on the story. An additional common pattern in this approach are pre-authored ''priority lists'' that order the outcomes from most to least likely and can, for instance, serve as tie-breakers.

* ''VideoGame/DragonAgeInquisition'': At the start of the game, the current [[HighPriest Divine]] of the [[TheChurch Chantry]] dies, and towards the end, three high-ranking members of the Inquisition announce their claims as her successors. As explained in-depth [[https://dragonage.fandom.com/wiki/Divine_election here]], each candidate has a hidden score (independent of the regular RelationshipValues) that starts out at 0 at the beginning of the game and goes up or down by anywhere from 1 to 10 points any time the PlayerCharacter makes a decision that directly or indirectly supports their future claim and preferred policies. The candidate with the most points at the end of the game is ultimately elected the next Divine in the epilogue, with a priority list reflecting their respective political clout used to break ties (from the most politically savvy to the least: [[spoiler:Vivienne, Leliana, Cassandra]]).

* ''VideoGame/ProjectTriangleStrategy'': The Scale of Fate subsystem branches your story (e.g. [[PlayerCharacter Lord Serenoa's]] decision to [[spoiler:surrender or to defend Prince Roland]] in chapter 7) based on a simple majority vote among all recruited and alive PlayerParty members (which characters join your army itself depends on an invisible three-point[[note]]Utility vs. Morality vs. Liberty[[/note]] KarmaMeter). Each party member has a preferred branch, but Serenoa can attempt to persuade some of them via dialogue to change their vote [[note]]though whether his persuasion attempt has been successful is not revealed until the vote actually takes place[[/note]], with his own (i.e. the player's) vote serving as a tie-breaker in case of a even split.

* ''VideoGame/ProjectTriangleStrategy'': The Scale of Fate subsystem branches your story (e.g. the decision of whether to [[spoiler:to surrender or to defend Prince Roland]] in chapter 7) based on a simple majority vote among all recruited and alive PlayerParty members (which characters join your army itself depends on an invisible three-point[[note]]Utility vs. Morality vs. Liberty[[/note]] KarmaMeter). Each party member has a preferred branch, but the main PlayerCharacter Serenoa can attempt to persuade some of them via dialogue to change their vote [[note]]though whether his persuasion attempt has been successful is not revealed until the vote actually takes place[[/note]], with his own (i.e. the player's) vote serving as a tie-breaker in case of a even split.

** ''VideoGame/MassEffect2'': In the final leg of the SuicideMission endgame, the surviving squad members who don't accompany Shepard to the FinalBoss battle hunker down to [[YouShallNotPass stop enemy reinforcements]] from catching up with Shepard. This entire battle occurs off-screen, but can have highly variable outcomes in regards to which squadmates survive: as explained in-depth [[Analysis/MassEffect2 here]], each squadmate has a hidden "HoldTheLine (HTL) score", ranging from 0 to 3 (incremented by 1-2 if their respective LoyaltyMission has been succesfully completed), and the number of casualties (ranging from zero to everyone) depends both on the total number of the defenders and on their ''average'' HTL score. After the game calculates the number of casualties, it selects the specific squadmates to die based on a priority list that, while not explicitly numeric, implicitly ranks them by their ability to survive[[note]]e.g. the SupportingLeader Garrus, despite his high HTL score, dies (likely by TakingTheBullet for a squishier member) before the lone wolf assassin Thane, whose HTL score is much lower[[/note]].

Most StoryBranching in VideoGames follows the classic {{Gamebook}} model of "choose X for branch A, or choose Y for branch B". More sophisticated narrative games implement {{Event Flag}}s to delay a specific decision payoff ("if you chose X earlier, event A occurs now"); multiple event flags can then be combined into an full ChoiceAndConsequenceSystem, and made arbitrarily complex with {{Promptless Branching Point}}s, a BranchAndBottleneckPlotStructure, etc. All of these tropes, however, fundamentally rely on [[https://en.wikipedia.org/wiki/Boolean_algebra boolean algebra]]: each player choice is its own true/false variable, and at every branching point, the devs must choose relevant variables and assign a specific outcome to every possible instantiation thereof ("if you chose X earlier or say Y now, event A occurs; otherwise, B occurs, unless you also chose Z, then C occurs"). As you can imagine, the complexity of this sub-system grows exponentially, the more choices the player can make.

This trope is about an alternative approach that uses numbers and simple arithmetic rules instead of boolean expressions to control story branching, whereby each decision made by the player increases or decreases one or more (often hidden) numerical scores. Then, when the time comes for the plot to branch, the game checks these scores and selects a branch based either on whether some value is in a specific, writer-defined range, or on which score is the highest at that point. This approach gives narrative designers a lot of expressive power by letting them add new meaningful player choices without having to explicitly account for every possible combination. Another benefit is that choices can now be ''weighted'', with some being assigned larger numeric modifiers than others, thus having a larger, but not dominant effect on the story. An additional common pattern in this approach are pre-authored ''priority lists'' that order the outcomes from most to least likely and can, for instance, serve as tie-breakers.

* ''VideoGame/EpicBattleFantasy5'': As explained in-depth [[https://epicbattlefantasy.fandom.com/wiki/Endings here]], the ModularEpilogue's scenes are initially determined by which of and whether the RelationshipValues between each possible pair of human {{Player Character}}s has reached certain numbers, with target values determined by number of completed achievements in its AchievementSystem, among other factors, but it will be the GoldenEnding if the achievement for beating the FinalBoss is beaten on the HarderThanHard "Epic" difficulty has been acquired, in any game, or if the party is a {{invoked}} SoloCharacterRun or two-person party ChallengeRun.

** ''VideoGame/FireEmblemAwakening'': Most characters don't get married unless the player selects the unlocked S support conversation scene. However, at the end of the first half of the game, there is a cutscene in which Chrom proposes to the unmarried love interest he has the highest [[RelationshipValues Support level]] with. Support points[[note]]gained by fighting next to each other or casting spells on or Dancing for the other[[/note]] count regardless of whether the player has viewde the support conversations they unlock, as there's no chance to view Chrom's supports with Olivia before this point, but she's still a viable option. If he has no support points with any free option, he'll instead get married to a generic village maiden NPC.

* ''VideoGame/PrincessMaker1'': The PlayerCharacter has seven {{Stats}} and a [[KarmaMeter Reputation]] score, and the combination thereof at the end of the game determines which of the [[MultipleEndings 30 endings]] she gets. Specifically, if her Reputation is 1200 or more, she gets the [[GoldenEnding Ruling Queen ending]]; and if it's between 800 and 1199, the Princess ending. Otherwise, the ending is based on which Stat is her highest and, again, on her Reputation: each Stat has four endings, from the worst (0 to 49 Rep) to the best (400-799 Rep).

* In VideoGame/WayOfTheSamurai4, there are three factions the player can help throughout the first three days. The game keeps track of which missions the player completes, as well as if a player angers a certain faction through their choices. On the fourth day, the game will use these factors to calculate which side the player is most loyal to, and have them represent the faction in a battle tournament before moving on for their side’s endgame. If the player doesn’t complete enough missions for any side, they’ll be given a neutral story that cuts itself off after the TournamentArc.