''Star Ocean'' is a series of {{Role Playing Game}}s developed by [[Creator/TriAce tri-Ace]] and published by Creator/SquareEnix.[[note]]Enix before the merger.[[/note]] All of them are set in the same universe, a high-tech SpaceOpera, but all of them spend a significant amount of time focusing on a [[MedievalEuropeanFantasy low-tech, high-magic world]]. The games are known for their fast-paced, real time battle system, and for the Private Action system that allows the main character to interact with party members in cutscenes while in towns. These can affect the ending through changing RelationshipValues.

The games in the series are:

* ''VideoGame/{{Star Ocean|1}}'' (1996)
* ''VideoGame/StarOceanTheSecondStory'' (1998)
* ''VideoGame/StarOceanTillTheEndOfTime'' (2003)
* ''VideoGame/StarOceanTheLastHope'' (2009)
* ''VideoGame/StarOceanIntegrityAndFaithlessness'' (2016)

There is also a 2001 game for the UsefulNotes/GameBoyColor titled ''Blue Sphere'' ([[IThoughtItMeant not to be]] [[SimilarlyNamedWorks confused with]] [[VideoGame/BlueSphere that one]]), taking place two years after the events of ''The Second Story'' with all twelve party members available. In December 2016, Tri-Ace released ''Star Ocean Anamnesis'', a mobile RPG game featuring both original characters of ''Anamnesis'' and returning characters of all five ''Star Ocean'' Games.

So far, every game except ''The Last Hope'' and ''Integrity and Faithlessness'' has had a manga adaptation.

There is also an [[TheAnimeOfTheGame anime]] based on the second game's manga adaptation, entitled ''Star Ocean EX''.

Most famously, the creator of this series were the original creators of the ''VideoGame/TalesSeries'', leaving [[Creator/BandaiNamcoEntertainment Namco]] due to the ExecutiveMeddling they encountered during the development of ''VideoGame/TalesOfPhantasia''. The first game is practically a SpiritualSuccessor to ''Tales of Phantasia'' where the battle engine is concerned.

!!This series as a whole provides examples of:

* AbsurdlyHighLevelCap: The max is usually 255. ''The Last Hope'' drops it to 200 initially, but you can bump it back up to 255 once you acquire enough Battle Trophies. For perspective, it's unlikely you'll be near 100 when you finish a game. That being said, [[NintendoHard You'll want every last level you can get for the]] [[BonusDungeon Bonus Dungeons]].
* AlienNonInterferenceClause: The Undeveloped Planet Preservation Pact ([=UP3=]).
* AnachronicOrder: The events of the series as a whole do not happen in the order of the games' release and can be quite confusing if taken as such. The in-universe chronological order is: ''The Last Hope'' (S.O. 4), S.O. 1, ''The Second Story'' (S.O. 2), ''Integrity and Faithlessness'' (S.O. 5), and ''Til The End of Time'' (S.O. 3).
* ArchaicWeaponForAnAdvancedAge: The series likes this a lot. In the [[VideoGame/StarOcean1 first]] and [[VideoGame/StarOceanTheSecondStory second]] games, this is justified by the protagonists being on planets protected by an AlienNonInterferenceClause. The [[VideoGame/StarOceanTillTheEndOfTime third game]] has the same justification (the protagonist ends up landing on an underdeveloped planet in an escape pod, being rescued by the crew of a ship, then crash landing on another underdeveloped planet and spending a good amount of time there), but halfway through the game you return to "developed" space, and yet many of the protagonists continue to use anachronistic weapons. In the [[VideoGame/StarOceanIntegrityAndFaithlessness fifth game]], you spend almost the entirety of the game on an underdeveloped planet, with sporadic periods in space.
* {{Bishounen}}: In every game. To name just one example from each, there's Ioshua from ''First Departure'', Dias from ''The Second Story''/''Second Evolution'', Albel from ''Till the End of Time'', and Faize from ''The Last Hope''.
* BonusBoss: This series is infamous for the amount of grinding you'll need to engage in if you want to stand a chance against them. The fact that your [[{{Cap}} maximum level]] in the first three games is ''255'' doesn't help matters.
* BonusDungeon: Sometimes multiple, almost always ''huge''.
* CallingYourAttacks: In pretty much any game with voice acting.
* CatGirl: The Lesser Fellpool race on the planet Roak and the variety of Fellpool on Expel.[[note]]Fellpool on Roak are essentially pointy-eared humans with tails, rather than having cat ears.[[/note]]
* ConflictKiller: Too many to list. There seems to be a veritable revolving door of villains in this series.
* CooldownManipulation: The games' Fury Gauge denotes how many actions they can take in battle, with the character needing to stand still for it to refill (attacking expends Fury, moving prevents it from refilling). Some skills allow the player to limit Fury use by certain percentages and amounts to pile on more hits.
* DayOldLegend: The games do this a lot. It's possible you're just recreating the item for whatever planet you're on; and the FlavorText is aimed at us, the audience; but still.
* DoingInTheWizard: Anybody from TheFederation in all three games will have a {{Technobabble}} explanation for magic -- or "symbology" or "heraldry", as it's usually known. For instance, Claude's "Sword of Light"? Actually just his phase gun.
* EvolvingAttack: Many of the Killer Moves, especially in ''The Second Story''.
* TheFederation: It's rather obvious in the first game they're not even pretending not to rip off ''Franchise/StarTrek''.
* FunctionalMagic: Symbology.
* GenreShift: For a series that's supposed to be set in outer space, you spend an awful lot of time on undeveloped fantasy planets. The fact that the fourth game has space travel as a core gameplay concept could almost be a GenreShift in and of itself.
* GlobalCurrency: Every planet seems to use Fol as its currency, regardless of technological development or location or even inbetween the several hundred years between installments. [[spoiler:Of course, given their universe is an MMO whose players use the same currency themselves, it not only makes sense, it also implies everyone playing it is [[BribingYourWayToVictory bribing their way to victory]].]]
* GuideDangIt: Could very well be renamed ''Guide Dang It: The Series'' due to the sheer amount of stuff (including items, skills, and ''recruitable characters'') that can be missed unless you know ''exactly'' what you're doing at any point.
* HelloInsertNameHere: The series allows you to rename the characters from the Status Menu, meaning you can do it any time you want. This aspect is completely averted in the UsefulNotes/PlayStationPortable remakes: no matter what you rename your characters, the voice acting still uses the canon names.
* HumanAliens: The series has quite a few of them. Some have wings, some have a third eye on their forehead, some have three black rings around their necks, and some just plain look human, more or less indistinguishable with the humans of Earth. In particular, Cliff's race, the Klausians, are naturally physically stronger than regular Humans, and as such have been limited to what events they can compete in during the Olympics. One thing worth noting is that all these aliens are ''classified'' as "Human" as the biological archetype, and from there you get the sub-races, including Earth's own Terrans.[[note]]There are also non-human humanoid races, such as the raccoon-like Medonix, that are simply collectively referred to as [[ExactlyWhatItSaysOnTheTin humanoids]].[[/note]] This makes a lot more sense once certain revelations in the third game are considered.
* InevitableTournament: All four games, though only the second game ''forces'' you to compete.
* InstantMessengerPigeon: Used as the main postal system, and to go shopping in the field.
* ItemCrafting: Each game has an Invention system that varies in mechanics from game to game.
* KiManipulation: The third game's in-game dictionary reveals that all Killer Moves are performed by the user drawing on their physical energy, as opposed to the mental energy that powers symbology..
* LimitedMoveArsenal: Type 1.
* LinearWarriorsQuadraticWizards: Somewhat averted. The first two games, especially the enhanced remakes, let you surround tough enemies and just beat them up with melees while the mages try to cast their symbology.
* LittleBitBeastly: Fellpools are humanlike in appearance, but have heightened senses and tails like cats. In fact, the series is full of these. [[CatGirl Fellpools and felinefolk]] are the most prominent, probably followed by [[WingedHumanoid featherfolk]], but less-common species are represented, too -- Roger in ''Till the End of Time'' is a LittleBitBeastly raccoon boy.
* MacroGame: Battle Trophies, voice samples and the MonsterCompendium are all shared between save files.
* ManaPotion: Blackberries, as well as some food and drink.
* ModularEpilogue: The games are will often show different ending scenes per party member depending on their relationships with other characters.
* MultipleEndings: The franchise is known for this. This is averted in the fourth game in favor of an unlockable WhereAreTheyNowEpilogue for each character.
* OneSteveLimit: Averted: the Ten Wisemen in ''The Second Story'' all have angel names, including Lucifer and Gabriel, but the boss of the bonus dungeon in the same game is ''also'' named Gabriel. ''Till the End of Time'' also has another Lucifer (Luther in the English version), who is of no relation to the one in ''The Second Story''. ''Till the End of Time'', at least the Japanese versions, use various demonic names for the Sphere staff (Azazel, Beelzebub, Belial). The same also applies to ''The Last Hope''. Apparently, the names of the Grigori are based on fallen angels from biblical apocrypha.
* OptionalPartyMember: In most ''Star Ocean'' games, there are several optional party members; you can have up to 8 characters, and usually 4-6 are permanent, leaving the extra slots to be filled up by a moderately extensive list. Getting some help you get others, and they ultimately affect the outcome and ending.
* PartyInMyPocket: Played straight for the most part. The fifth game averts this by having all party members in the field at all times.
* PowerTattoo: In most cases, use of symbology requires a person to tattoo special symbols on themselves, although carving them into a personal weapon also works.
* RidiculouslyCuteCritter: Bunnies.
* SavingTheWorld: Or universe. No spoilers needed.
* SpaceElves: The Nedians in the second game and the Morphus in the fourth fit both the Elves In Space and Enlightened Mystic Race versions. [[spoiler:They are heavily implied to be the same species.]]
* StuckItems: Phia and Ioshua's accessories from ''First Departure''. Try as you might, you can't take that damn ring off.
* SpaceIsAnOcean: The name of the entire series. [[TitleDrop Directly referred to]] in [[VideoGame/StarOcean1 the first game]] and [[VideoGame/StarOceanTheLastHope the fourth]].
* SquadControls: You can control what your party members do in battle from the menu screen. It's pretty basic, however, as you call ask them to focus on certain patterns and formations.
* SpiritualSuccessor:
** There are major similarities between ''Star Ocean'' and the ''VideoGame/TalesSeries'' in gameplay and design: real time battles with combat skills that burn MP, item creation, food-based healing items that heal in percentages, Private Actions / Skits, RelationshipValues leading to MultipleEndings, and so on. This is because ''Star Ocean'' was created by tri-Ace, a company whose founding members are best described as "Basically everyone who designed ''VideoGame/TalesOfPhantasia'' at Namco."
** ''Star Ocean'' is a spiritual successor of ''Franchise/StarTrek''. A developer mentioned that the ''Star Ocean'' series was actually first created with ''Star Trek'' as main motivation.
* TimeTravel:
** The Guardian allows this. Again, not even bothering to differentiate from ''Star Trek''. However, its function is expanded greatly in the third game.
** Time Travel becomes a part of the plot of ''The Last Hope'' when [[spoiler:a wormhole within a black hole sends the crew back in time to planet Earth in the year 1957. After the crew escapes from Earth as the planet itself is being reduced to antimatter, the crew realizes that the Earth through the wormhole was nothing more than an alternate dimension. Of course, this doesn't make Edge feel any better knowing that handing over the ship's energy core for research to save the future led to the planet's complete destruction. Cue HeroicBSOD.]]
* TitleDrop: ''The Last Hope'' is very guilty of this for their subtitle, though ''First Departure'' does it too. Both games also drop in the term "Star Ocean" during dialogue.
* {{Tsundere}}: That would be Millie and Reimi of ''First Departure'' and ''The Last Hope'', respectively. Both are the canon heroines.
* UpdatedRerelease:
** The second game was given a port for PSP in 2008, with similar enchancements that the remake of the first game for same console had.
** The fourth game was later released for the UsefulNotes/PlayStation3 with some new features and characters.
* UselessUsefulNonCombatAbilities: Of the "Optional" variety. You can beat the game without investing a point into any non-combat skills. If you do invest time into them, however, you'll ''reap'' the rewards.
* VideoGameRemake: The first game was remade in 2007 with ''The Second Story''[='=]s style for PSP, and in 2008 it got the first official release in North America and Europe.
* WingedHumanoid: The Featherfolk race.
* WitchSpecies: While most species require specialized tattoos to use symbology, there are a few that already have the symbols etched into their very DNA.
** The Featherfolk, Nedians, and Morphus are some examples of species that see this happen in most, if not all, of their members.
** Lemurisians occasionally see this happen in a small minority of their women.
** This also started happening to a small minority of Expellians [[spoiler: after they absorbed the remnants of the Nedians.]]
* YouGottaHaveBlueHair: Unsurprising, given the series' anime-ish style; in fact, at least two party members in every game have literal blue hair, including the male leads of the first, third and fifth games. In most cases, this can be justified by the fact that they are aliens [[spoiler:or genetic experiments]], though not always.