-->''This is the Inner Sphere, thousands of planets colonized by humankind. Once it was united under the Star League, but for the last three hundred years it has been consumed by savage wars...''
--->-- '''Adam Steiner''', from the ''BattleTech'' animated series.

A galaxy-wide conflict with GiantMecha spanning centuries is ripe for backstory, so [=FASA=] naturally encouraged filling out the BattleTech universe. They licensed the creation of a series of ScienceFiction novels as the main medium for this. The continuity of these novels was incredibly well kept, mainly because the nature of the 'verse allowed for a very wide variety of characters and settings. Naturally, this led to an [[LoadsAndLoadsOfCharacters extremely large and diverse cast of characters]], which is probably the strongest point of the novels. Much of the setting's tone was (and continues to be) defined by MichaelStackpole, with other authors fitting their works in around his.

The novel series of the setting (which are far, ''far'' outnumbered by individual novels) include, in rough in-universe chronological order:

* The ''Saga of the Gray Death Legion'' trilogy (Creator/WilliamHKeithJr)
* The ''Warrior'' trilogy (Stackpole)
* The ''Blood of Kerensky'' trilogy (Stackpole)
* The ''Legend of the Jade Phoenix'' trilogy (Robert Thurston)
* The ''Twilight of the Clans'' series (multiple authors, including Stackpole and Thurston)
* The ''Capellan Solution'' duology (Loren L. Coleman)
* The ''Fortress Republic'' duology (Coleman)

In addition, [=FASA=] licensed a number of video game series based on the universe. These, especially the MechWarrior series, turned out to be widely popular, and drew more people into the franchise.

The video games include:

* The ''VideoGame/MechWarrior'' series
* The ''VideoGame/MechCommander'' series
* The ''VideoGame/MechAssault'' series
* ''[[http://mwomercs.com MechWarrior Online]]''
* ''[[http://mwtactics.com MechWarrior Tactics]]'' -- the first ''commercial'' implementation of the boardgame rules

On top of all of this, 1994 saw the release of the AnimatedAdaptation, [[NamesTheSame also called]] ''[=BattleTech=]''. Set during the war against the Clans, it focused on a military unit led by Adam Steiner. It was later {{RetCon}}ned as being a [[LiteraryAgentHypothesis propaganda account of events that actually happened]], with Adam Steiner and at least one other character showing up in the novels.

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!!These works [[note]]tropes specific to the video games are listed on their pages[[/note]] provide examples of:
* AbsentAliens: A few novels (most notably ''Far Country'') actually do have aliens. The rest? None.
** For ''Far Country'', the aliens in question live in a system that's only been accessed by humans twice, both in jumpship mishaps that leave the humans stranded there. So they exist, but they can't interact with the rest of the Battletech universe.
* AdaptationDecay: The animated series was retconed as an in-universe, "poorly reviewed Anti-Clan propaganda holo-vid".
** A later sourcebook explains it as based on real in-universe events, but suffering among other things from AnachronicOrder due to drawing inspiration from events that hadn't happened ''yet'' in the timeframe depicted.
* AwesomeMcCoolname: Grayson Death Carlyle.
* BullyingADragon: Novel ''Close Quarters'' has the main character, Cassie, use a bolter on a battlemech to provoke it into chasing her. The metallic ping against the cockpit window is a [[BatmanGambit direct insult to the mechwarrior's arrogance]], which causes them to give chase. She runs through a few buildings before surprising the mech with an electrical attack to the knee joint. The electricity spot-welds the joint, and crashes the mech to on the ground. She repeats the same action later in the novel by attracting a mech into swampy terrain where it gets stuck and crashes onto the ground.
* BadAss: Too many to list them all. It's pretty much a requirement for surviving the front lines in combat. Kai-Allard Liao is probably the most noteworthy example (see MemeticBadass below).
* CanonDiscontinuity: The Battletech Animated Series, as described above. However, some characters, notably Adam Steiner, became {{Canon Immigrant}}s.
* CanonImmigrant: As mentioned above, some of the Animated Series characters obtained this status. Adam Steiner is easily the most visible of them. Also of note are Vandervahn Chistu (Nicolai Malthus' superior) and Franklin Sakamoto. Chistu would briefly become one of the Falcon clan Kahns, ultimately dying at Vlad Ward's hands during the Refusal War. Sakamoto, on the other hand, would survive until the early stages of the Jihad in 3070. (Worth noting that Sakamoto was captured by the Black Dragon forces, with his ultimate fate apparently remaining unknown.)
* CatchPhrase: From the cartoon: "Information is Ammunition." (Also featured in passing as a MythologyGag in the novels)
** Also from the game itself: "No Guts, No Galaxy"
* ChangelingFantasy: Subverted - Franklin Sakamoto renounced his claim to the throne.
* TheChessmaster: Subhash Indrahar, head of the Kuritas SecretPolice for ''60'' years.
* ConspicuousCG: The cartoon's very poorly done [=BattleMech=] rendering sequences. Though they at least got the ponderous weight of 'Mechs right. The animated 'Mech combat looks like anime-style movement.
* CriticalExistenceFailure: The concept of Combat Loss Grouping; stastistically, mechs of a similar weight class will continue to fight for long periods of time before becoming combat ineffective all at once.
* CutShort: The animated series ended on an unresolved CliffHanger.
* DefeatMeansFriendship: A common method for mercenary units looking to recruit people.
* DefectorFromDecadence: [[spoiler: Trent of Clan Smoke Jaguar. Having been a victim of politics several times (his sibmate changes the official report of the battle of Tukayyid, and then manages to steal his spot on the Trial of Bloodright), with the help of his bondsman, he manages to escape his Clan, goes to ComStar and gives them the Exodus Road, the path to the Clan homeworld.]]
* DysfunctionJunction: The Seventeenth Recon Regiment, aka "Camacho's Caballeros". Their top scout is a recovering sociopath, one of their best captains is a repeated rape victim, another is clinically insane (and proud of it), and their commander is grieving his deceased daughter while his surviving son suffers from WellDoneSonGuy.
* EverythingsLouderWithBagpipes: The Northwind Highlanders have their bagpipe band play the loudest song possible onto Clan Smoke Jaguar radio frequencies to jam up the Clan's communications, forcing the Clanners to use more troublesome line of sight based communications.
* {{Expy}}: Johnny Tchang is a straight one of both BruceLee ''and'' JackieChan. One of his films is even called ''[[EnterTheDragon Exit The Dragon]]''.
* FakingTheDead: Galen Cox. [[spoiler:It's part of an elaborate scheme to expose Katherine Steiner-Davion's duplicity.]]
* GoodColorsEvilColors: Inverted in the animated series, under enhanced imaging Clanners look green while the Inner Sphere are red. Presumably because it's Clan tech that the "good guys" didn't have access to until halfway through the series.
* GoodIsNotNice: Again, too many to list. GrayAndGrayMorality is a big part of life in the Inner Sphere.
* GuileHero: Adam Steiner, who in the animated series, considers accurate intel to be the most powerful weapon around and isn't above manipulating rival clans into fighting each other while his crew quietly escape.
* HappilyMarried: Hanse might have married Melissa for political reasons, they did make it work and love each other.
* HeelFaceRevolvingDoor: Tormano Liao. Basically, he's on whatever side is against the Capellan Confederation at the moment.
* HonorBeforeReason:
** Common with the Clan warriors and the older-line Draconis Combine warriors and nobility.
** Also, this is why Myndo Waterly thinks that Anastasius Focht won't [[VillainBall just shoot her]]. [[spoiler:She's wrong.]]
* ImpossiblyGracefulGiant: The first BattleTech novels had mechs doing rolls, going prone, and doing other silly maneuvers. Later novels makes them much more [[WalkingTank tank-y]] like in the boardgame.
* KillItWithFire: One of the most effective anti-Mech weapons an infantryman can carry is the Inferno rocket, which is loaded with a napalm substitute that overheats the Mech and cooks the pilot inside. As a result, fear of death by fire is common among [=MechWarriors=].
* KilledOffForReal: Takashi Kurita, Subhash Indrahar, [[spoiler:Omi Kurita]]
* ManipulativeBitch: Katherine "Katrina" Steiner-Davion. [[spoiler:For example, she seizes control of an entire interstellar nation just by rigging their popularity polls.]]
* MechaShow: The animated cartoon.
* MemeticBadass: In-universe, Kai Allard-Liao. To the point where Clan commanders sending fifty [[SuperSoldier Elementals]] to hunt him down (while he's injured, without a 'Mech, and on the run behind enemy lines), is considered a "fair fight".
* NamesToRunAwayFromReallyFast: Ninyu Kerai. Subhash Indrahar apparently used to be one before old age caught up with him.
* NiceJobFixingItVillain: In ''Mercenary's Star'', [[spoiler: a Kurita assassination attempt on a Lyran ambassador is exactly what convinces said ambassador to send reinforcements to the Gray Death Legion]].
* ThePlan: Just like being a BadAss seems to be a requirement for surviving warfare, mastering gambits seems to be required for successfully holding any kind of political power.
* RoyallyScrewedUp: Both the Liaos [[spoiler:until Sun-Tzu]] and the Kuritas [[spoiler:until Theodore]] are this.
* RuleOfCool: The actual rules of the original game frequently get tossed aside in favor of this. Hey, [[TropesAreTools whatever works...]]
** Some of these incidents, such as an Atlas throwing the much smaller Locust around like a rag doll (often alluded to in fluff) were [[AscendedFanon finally canonized as game rules to get players to stop complaining about not being able to do what was in the fiction.]]
** Also subverted; the climatic action sequence of '''Grave Covenant''' and most of the 'Mech combat sequences that don't involve Morgan Kell or Yorinaga Kurita in the Warrior Triology appear to have been actually gamed out under the tabletop rules. The '''Grave Covenant''' scene with Victor's ''Daishi'' and Renny Sanderlin's ''Penetrator'' is even in one of the scenario books.
* SirSwearsalot: Clan pilots. Expect Clan character's dialogue to be about 20% cussing (in the Clan's vocabulary, which means loads and loads of "FREEBIRTH" and "STRAVAG" being yelled)
* StarCrossedLovers: Justin Allard and Candace Liao (who end up HappilyMarried and produced the aforementioned MemeticBadass Kai), and later Victor Steiner-Davion and Omi Kurita ([[spoiler:which doesn't end nearly as well]]).
* StockholmSyndrome: [=POWs=] of the Clans start out as bondsmen, but are given the chance to regain their warrior status if they pass a TrialByCombat, upon which they become a fully fledged member of the capturing Clan. The most extreme example would be [[http://www.sarna.net/wiki/Phelan_Kell Phelan Kell]] a captured Inner Sphere mercenary (the Clans viewed these as the lowest form of scum) who not only earned his own bloodname (and by that, I mean he had a bloodname ''named after him''), but would go on to become the leader an entire Clan subfaction.
* StoryArc: Done by the animated series, which was noteworthy for American animation of the time.
* TheReveal: The history of the Clans, and the nature of Wolf's Dragoons.
* UnresolvedSexualTension: Kai Allard-Liao and Deirdre Lear. [[spoiler: That would be until they got married. Or possibly earlier.]]
** [[spoiler: Their son, David Lear, was born shortly after they separated on Twycross, long before they got married. Kai was ''unaware he had a son'' for a while. So definitely earlier.]]
** Also a very "star-crossed lovers" example in Victor Steiner-Davion and Omi Kurita. They fall in love with each other at just about first sight when meeting on Outreach, but he's the heir to the Federated Commonwealth and she's the daughter of the Coordinator of the Draconis Combine and they're both too conscientious to just shirk their responsibilities in the name of romance... [[spoiler:They do get together in the end, although eventually an assassin sees to it that it doesn't last forever.]]

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