ME1:
Beatrix sees casualties - civilian or otherwise - as often necessary and does not go out of her way to prevent them. She is a firm believer in the greater good and jeopardizing a mission in any way to save people angers her. She likes taking action and hates politics and red tape. Despite her distaste for corruption, she is not above covering things up or doing dirty work in the name of the Alliance.
Beatrix disagrees with the ideology of anti-alien/pro-human organizations, like the Terra Firma party or Cerberus, and is willing to serve alongside aliens, but that is a low bar and she holds some xenophobic ideas about aliens. She dislikes what she sees as the Asari's superior attitude and judges the Quarians for their creation of the geth, being actively against the existence of AI. Beatrix prizes self-preservation and protection and is not prone to self-reflection. She automatically distrusts what she doesn't understand and thus what could pose a danger to her, one of the main reasons for her prejudices against aliens. It also manifests in a wariness of biotics and more experimental science. Despite her own lack of moral conviction in many areas she is actively against unethical science and anything she considers "playing God," such as the creation of AIs (and, in theory, the genophage).
Hot-headed, aloof and always teetering on the edge of impatience, Beatrix takes command of the Normandy with a single objective: stop the rogue Spectre Saren at all costs. Whenever she had been part of a crew, Beatrix never made an effort to get to know them and even in the position of the Normandy's XO, she was under no impression that pattern would change. The only person she truly trusts and fully respects, and therefore is consistently respectful to, is Captain Anderson. Only after taking command and having to work more closely with her subordinates does she feel the need to learn about them personally -- but often only soshe knows how they could help or hinder the mission. Underneath her hard personality she has a scientifically geared mind and is ultimately a curious person, another reason she inquires about her crew. She dislikes when this objective interest is seen as friendly overtures.
Beatrix undergoes a surprising if still ultimately subtle change while hunting Saren. No longer able to remain completely removed from other people, she slowly begins to trust and, in some cases, even like her crew. With aliens making up most of it, Beatrix is also forced to face her prejudice and ignorance surrounding them. By the defeat of Sovereign, Beatrix is by no means free of xenophobia but much of it has dissipated. She also becomes less wary of biotics. Her opinions on controversial science do not change and in fact her encounters with Cerberus only reinforce them. Another change comes in her willingness to try to minimize casualties, like when she tries to not kill the brainwashed colonists on Feros and spares the Rachni Queen, as having a direct hand in the extinction of an entire species goes too far even for her. Less upsetting to Beatrix is the decision to sacrifice the Council to focus on Sovereign, a strategic move to stop the Reaper rather than a ploy to give humans control of the Council.
She comes to trust Joker, Kaidan, and to a lesser extent the remaining aliens onboard. Of note is her relationship with Liara, a person she doesn’t trust at all initially due to her ties to Benezia but whose sincerity is affecting enough that Beatrix finds herself getting feelings. By the time of the attack on the Normandy, Liara is the only person in the world besides Anderson who Beatrix absolutely trusts. Along with Liara, Beatrix eventually gets along well with Garrus in particular, whose "do whatever must be done" attitude she likes and encourages. With actual friends for the first time, Beatrix is more respectful, if still nowhere near warm or cuddly, to people she likes. She also loosens up and her humorless and reserved demeanor softens slightly to reveal a still rarely seen sense of humor.
ME2:
When Beatrix is resurrected by Cerberus, she is initially repulsed by the idea of working with them. She grew to despise them after their run-ins in her hunt for Saren, but she ultimately agrees. This aligns with her belief in sacrificing things -- in this case, her personal feelings and morals -- for the "greater good". Stopping the Collectors, and thus the Reapers, is her first priority now. Since the galactic government is failing to act Beatrix allies with her previous enemy, although never once does she expect they don't have ulterior motives and won't betray her. She's glad she's not dead but it's not lost on her that she was brought back by scientists doing what she hates -- "playing God." Her hatred and distrust for The Illusive Man extend to the other members of Cerberus: Miranda, Jacob and the entire crew of the new Normandy, as well as EDI, who she especially distrusts due to her being an AI.
Beatrix finds herself dealing with a large variety of intense feelings. Not only is she reeling and disturbed after finding out she was dead for two years, knowing Cerberus Beatrix does not even 100% trust that she is herself. She feels trapped, resentful and ashamed working with Cerberus and the complications from doing so as well as her "return from the dead" only add to her distress. Beatrix does not approve of the human first agenda of the human government now that it's taken over the Council, a consequence she didn't intend with the destruction of the Destiny Ascension, nor is she happy with their denial of the Reapers. However, Beatrix is still loyal to the Alliance and no longer being a part of it is difficult for her.
Also difficult is the situation’s effect on her relationships. The first friendly faces she encounters when she comes back are Joker and Karin Chakwas, but rather than finding their presence comforting, she loses faith in them because they joined Cerberus. Both Tali and Kaidan's negative reactions to Beatrix are both reassuring and hurtful -- she is glad her former allies maintain their hatred for Cerberus, but she's nonetheless hurt by their wariness of her. Liara's refusal to join Beatrix, as well as the new distance between the two, greatly pains Beatrix and as someone very averse to vulnerability, Beatrix overcompensates by pulling away from Liara. In contrast, Garrus and eventually Tali’s belief in Beatrix despite their hatred for Cerberus cements her trust in them.
Beatrix goes through a bigger change trying to stop the Collectors than during her hunt for Saren, in large part because she's working with an organization she hates, a larger squad, and because she's forced to engage with their personal lives. For the first time, Beatrix trusts the aliens on her crew more than humans, as she can be sure that her alien squadmates are not in league with the anti-alien Cerberus, unlike Miranda and Jacob. When Grunt and Tali declare Beatrix their battlemaster and captain respectively, it means something to her.
The squadmate who makes the biggest impact on Beatrix is certainly Legion. Unlike her opinions on aliens, her dislike of AI has barely decreased as time's passed, even with the helpful EDI on board -- EDI's ties to Cerberus prevent Beatrix from allowing herself to like or feel comfortable with EDI after she's unshackled. The geth are especially bad in Beatrix's eyes and she doesn't have an interest in seeing the geth's viewpoint in history until Legion. Its presence forces her to do just this and by the time of the Suicide Mission, Beatrix's opinion on the geth has already softened. Unlike EDI, Legion is unaffiliated with Cerberus and so Beatrix grows to actually respect it.
Meanwhile, the distance Beatrix has put between her and Liara allow feelings for someone else to develop. After seeing the consequences of Zaeed's reckless search for vengeance against a former ally, Beatrix has a rare moment of insight into another person, in this case Garrus, and puts aside what she would personally do, instead saving Sidonis in Garrus' best interest. This experience not only affects Beatrix's experience with friendship in general but brings her closer to Garrus. Much of the distance between her and Liara closes after Beatrix helps Liara fight the Shadow Broker and although Liara's feelings for Beatrix are still present, the damage is too much for Beatrix. This, as well as her budding romance with Garrus, marks the end of their romance. Even so, the unique gentleness Liara always brought out in Beatrix remains.
By the Suicide Mission, Beatrix no longer dislikes anyone in her squad. She continues to distrust Miranda and Jacob, Jacob less so due to his clear hesitations about Cerberus and past with the Alliance. After the Collector Base, Miranda's rebellion against The Illusive Man makes her a true ally in Beatrix's eyes. One of the last straws in working with Cerberus is the Overlord project, which she find repulsive and puts a stop to. As soon as the Collectors are defeated, Beatrix disavows Cerberus and returns to the Alliance without hesitation. She is even glad to be on the same side as the Council again, although she quickly and painfully remembers their lack of action against the Reapers. She is also disturbed by what happens with Amanda Kenson and her ruthlessness does not mean that eradicating an entire batarian system is not horribly upsetting and shocking to her.
ME3:
Stripped of her ship and taken out of combat, Beatrix spends several months in near isolation. Eventually, her anger is replaced by bitter resignation; any faith she had in the government is now completely gone and she finds a sort of solace in the knowledge that she will soon be proven right. She indeed feels a strange sense of relief when the Reapers attack as it finally proves her right. Mostly, however, she feels incredible fear, pressure, and loss. She is relieved the government is finally taking action but her resentment limits sympathy for their struggles. She is furious she must deal with diplomacy and gathering allies and has no patience for politics. Beatrix no longer mistrusts aliens more than humans and is now self-aware enough to recognize previous prejudices. She is fully against Cerberus, but her loyalty to the Alliance is no longer set in stone - when it comes down to it, she cares only about defeating the Reapers.
Despite growing closer to her crew during the Collector mission, Beatrix finds it easier to avoid contact with them while grounded. She partially convinces herself she prefers it that way and puts distance between them as to avoid vulnerability. When reunited with some of the crew, the camaraderie returns and Beatrix finds the casual friendliness a good cover for the distance she is maintaining from them, as well as for the extent of her fear and sadness around the war. Beatrix refuses to allow those around her, especially people closest to her, to sense any these “weaknesses.” The pressure and horror of the war drains and hardens her and her previous ruthlessness comes back nearly in full measure - even if this time it comes with regret for what must be done.
Beatrix's changing morality battles itself during the war. Ultimately, she is willing to lie, manipulate and kill to accomplish her goals. Although she does desire to act altruistically, many of her decisions to do so come with an ulterior motive. She may not have tried to broker peace between the Geth and Quarian fleet if it was not for the prospect of having both fleets or gone out of her way to save Grissom Academy if not for the biotic students’ usefulness. It’s also for this reason that Beatrix doesn’t give Miranda access to Alliance resources, as it is not immediately clear how it'll help the war effort. Beatrix is genuinely upset at Miranda’s death but stands by her choice to withhold resources, maintaining that Miranda should have told her everything.
Indeed, unlike on Noveria, Beatrix foregoes saving the Rachni again because she considers them too much of a liability. She also does not reveal the genophage sabotage until Mordin confronts her, willing to let the cure fail for short-term war support. Face to face with Mordin, however, she is forced to see how despicable that choice would be and is unable to go through with the sabotage. Similarly, the only reason she hesitates and makes an effort to talk Kaidan down during the Citadel coup is their history. Even so, had he not backed down she would have taken the shot. Even her own face does not convince her to spare an enemy, as demonstrated by her lack of hesitation in killing her clone, which she deems an abomination and a reminder of her own insecurities around her resurrection.
With EDI no longer working for Cerberus, as well as her history with Legion, Beatrix's opinions on AI are drastically different and she contends that they are indeed people. Even with her great strides in trusting synthetic life, at the war's end when faced with how to handle the Reapers Beatrix sees "synthesis" as too much of an unknown and doesn't trust the idea. She also would never trust anyone, even herself, with control over the Reapers and doesn't want anyone to do so anyway - she wants to see them burn. Therefore it seems like a sick joke that after finally learning to value life, destroying the Reapers will destroy the Reapers' AI brethren. Beatrix ultimately remains faithful to her constant if subtly shifting philosophy - do what must be done no matter the cost - and destroys the Reapers. Afraid of Doctors: She doesn't want to be vulnerable or at anyone's mercy and thus does not like doctors.
Aloof Dark Haired Girl
A Million is a Statistic: her belief system.
Anger Born of Worry: Her yelling at Liara when the Normandy is crashing or at Garrus when he's injured at the end of ME3 show this. If you expect a tender, heartfelt moment from her in the midst of danger, you won't get one.
Anti Hero
Asskicking Equals Authority: She believes it does.
Badass Normal: Possibly negated when she gets her cybernetic implants, but otherwise Beatrix does not have biotics and only relies on weapons and her tech training.
Beauty Mark: Has several moles on her face.
Berserk Button: Beatrix is alright with a lot of questionable things, but when it comes to disrespect towards the Alliance, unethical science or someone putting their hands on Liara, watch out.
Birds of a Feather: Beatrix and Garrus. In ME1 their conversations are like an echo chamber, with neither challenging the other on their beliefs. Due to Character Development on both sides this changes slightly, but they both remain pragmatic snipers with a similar sense of humor and hatred of red tape. Also with Beatrix and Javik in ME3.
Blood Knight: One of the reasons she joined the Alliance. She loves fighting and given her temper and anger issues, it's a good way to work through them.
Brainy Brunette: Not much in the way of formal education, but she's intelligent, tactical and tech savvy regardless.
Brutal Honesty: She does not mince words.
Character Development: Significant. She doesn't do a full 180, but she is noticeably more approachable and thoughtful by ME3.
Closet Geek: Given her rough personality and jackboot persona, her interest in science, model building, and engineering are surprising to many.
Clothing Reflects Personality: Beatrix wears mostly dark colors, especially black, and even if not dressed in the Alliance uniform, there's usually an Alliance logo somewhere on her outfit.
Cold Sniper
Combat Pragmatist: She's a sniper, so being pragmatic in battle comes with the territory. It depends on who she's up against, but her idea of honor in battle tends to bend in favor of the most effective methods.
Cowboy Cop: More so Cowboy Marine, as Beatrix has a distinct dislike of cops.
The Cynic
Dark and Troubled Past: Had a challenging childhood and early adulthood.
Dark is Not Evil
Death Glare
Defrosting the Ice Queen: To an extent. While she never totally loses her harshness, she goes from disdain for almost everyone to having a handful of loyal friends she respects. Drill Sergeant Nasty: How she can behave towards her subordinates, particularly in ME1 and before.
Even Evil Has Standards: She may not be evil, but she can get pretty bad in ME1. Even so, she finds Cerberus reprehensible and is also firmly against Terra Firma. Similarly, she finds the unethical corporate dealings, like ExoGeni and everything on Noveria, to be disgusting. She also refuses to kill the rachni queen, drawing the line at eradicating an entire species.
Expository Hairstyle Change: Beatrix typically wears her hair in a bun, but during her time with Cerberus she wears it down. This represents her lack of respect for Cerberus and feelings of displacement and confusion. Her hair returns to an updo in ME3 when she's back working for the Alliance, but a loose one as she's still feeling at odds with herself and now her role in the war.
Eye Color Change: From light brown to a full-blown red orange glow.
Fire-Forged Friends: Most of her squad mates-turned-friends, particularly the aliens and Miranda and Jacob.
Foil: Kaidan. Both are extremely loyal to the Alliance, are the only human Spectres, and don't back down from their values. The difference is Kaidan values integrity, honor, and respect, while Beatrix is more about pragmatism and the greater good. Neither is afraid to confront the other on what they disagree with: Kaidan on what he sees are harmful views or actions and Beatrix on what she considers his naïveté and idealism. Also Zaeed in ME2.
Former Teen Rebel: Used to run with gangs and is open about and mostly unashamed of it.
Friendless Background: Besides some camaraderie with fellow gang members and soldiers, before ME1 Beatrix never had or wanted any actual friends.
Freudian Excuse: Beatrix grew up with somewhat negligent parents, became an orphan and then ran with gangs until she was 18. She has quite a few issues with trust and anger.
Genius Bruiser: Downplayed. Beatrix isn't showy about her intellectual side, but she's extremely proficient in tech, curious, and likes chess, puzzles, and building model ships. She's a bit of a nerd, although you wouldn't guess it.
Good is Not Nice
Good is Not Soft
Good Scars, Evil Scars: Both arguably. Her scars are more visible due to her ruthless actions, but she's ultimately on the side of good.
The Gunslinger: Extremely good with a sniper rifle and won't let anyone, even the love of her life (Garrus), forget it.
Heartbroken Badass: Most obviously in ME2 after most of her ME1 squad has moved on including her ex Liara. She doesn't even allow herself to be heartbroken in ME3.
Heroic BSoD: By the end of ME3, she's so exhausted and put out that she's pretty much just going through the motions.
Hidden Depths: Seems like a typical “Cowboy Cop” soldier but is a bit more than that.
Hot-Blooded: Has an extremely hair-trigger temper.
Hot Scientist: Not a scientist per se, but she specializes in tech and is definitely not bad to look at.
Hurting Hero: Her situation in ME2 when many of her reluctantly made friends have moved on and won't join her again or even trust her. This, plus her anxieties and guilt around being rebuilt and working with Cerberus, and she doesn't handle it well.
Hypocrite: She disapproves of police brutality and corruption in general even though she herself often uses her authority to inflict unnecessary violence on people and go above the law if it suits her. She also hates cops but considers the military to be honorable and largely above reproach.
Interspecies Romance: Pre-ME1 she only had sexual experiences with humans. Over the course of the trilogy this changes and she has vastly more flirtation with aliens than humans. She seems to be particularly attracted to the asari.
I'm Not Here to Make Friends: Her attitude in the beginning of ME1 (and ME2). She mostly fails.
Indifferent Beauty: Beatrix usually doesn't care if she's found attractive.
I Work Alone: At least she wants to in the beginning. She's fine with fighting alongside others as is typical for the military, but she doesn't want any camaraderie.
Jerkass: Much more obvious in the first game when her hair trigger temper means she can be seen shoving civilians against walls and threatening every other person. She still fits this trope in later games, but it's downplayed and the behavior is less widely applied.
Jerkass Has a Point: Much of her hatred for Cerberus is this, especially in ME1. She also makes a good point to Wrex about Saren’s use of the krogan, even if she doesn't articulate it in the most diplomatic way.
Knight in Sour Armor: She’ll save the world but will yell at everyone while doing it.
Like an Old Married Couple: She and Garrus. Also she and Liara, strangely more so after they break up.
Morality Pet: Liara to Beatrix. Tali to a lesser extent.
Murder is the Best Solution: Her initial philosophy. It doesn't change completely, but as early as ME1 she becomes more open to other ways of dealing with situations.
No Social Skills: Tact? Never heard of it. It's lucky she's so good at intimidating people, as her charm and general ability to understand and be compassionate towards others is nearly non-existent.
Not Good With People
Odd Couple: With Liara in ME1. Liara is quiet and gentle while Beatrix is... not those things. It's probably difficult to understand to outsiders why either one would be interested in the other.
Odd Friendship: Beatrix with quite a few of her squad mates.
One Woman Army: It's no surprise she's sent on so many solo assignments.
Parental Abandonment: Her father abandoned her when she was young and her mother died soon after. She barely remembers them.
Parental Substitute: Anderson is undoubtedly a substitute parent and is the first and one of the only people Beatrix shows genuine, unwavering respect towards.
Platonic Life Partners: With Liara after they've broken up.
Pragmatic Hero
Raven Hair, Ivory Skin
Red Eyes, Take Warning: Obviously the case once her cybernetics turned her eyes red, but even before she was reconstructed, her brown eyes had a distinct reddish hue to them.
Redi Oni, Blue Oni: Red Oni to The Illusive Man’s Blue Oni. Beatrix is a passionate, brash soldier who hates niceties and diplomacy and, as the Illusive Man would say, only sees the world down the barrel of a gun. Besides her loyalty to the military, she’s generally anti authority. The Illusive Man, meanwhile, is a calculating figure who cultivates an air of mystery and culture. He puts up a calm facade but desires control and authority.
Reformed Criminal
Rescue Romance: The root of her romance with Liara, though it blossoms into something more substantial.
Safety in Indifference: One of the primary reasons she avoids getting to know people. This is also the biggest reason behind her breakup with Liara.
Satisfied Street Rat: Beatrix suffers from issues stemming from her tough childhood but all in all is okay with it and alright with herself.
Scars Are Forever: Averted with her scars in ME1 which disappeared during her reconstruction. Her cybernetic scars, however, last indefinitely.
Screw the Rules I'm Doing What's Right: At least what she thinks is right. She usually avoids doing this with Alliance rules, but everything else is fair game.
Silly Rabbit, Idealism is For Kids
Street Smart
Tank Top Tomboy: Wears a black N7 tank top as her casual outfit in the second and third game. Conveniently shows off her muscular arms.
Teeth Clenched Teamwork: With the alien crew in ME1, Cerberus in ME2, and the Council for the entire trilogy.
Tomboy and Girly Girl: With Liara.
Tomboy with a Girly Streak: There are instances where Shepard is shown happily wearing dresses and makeup.
Too Much Alike: Beatrix and Jack are cut from the same cloth. Both are angry, orphaned loners with criminal pasts who hate Cerberus, enjoy violence, had troubled childhoods and have a 'kill or be killed' mindset. But their shared lack of patience and interest in niceties mean they end up butting heads more often than not and both are intent on maintaining the upper hand due to their control issues. They both mellow out a bit by ME3 and get along better, but never fully.
Took a Level in Cheerfulness: Seen especially in Citadel when she hangs out socially with multiple crew mates while in a good mood. This is a big departure from what you'd expect from her in ME1.
Took a Level in Jerkass: After taking A Level in Kindness in ME2, in ME3 the stress of war means she reverts back to a lot of her ME1 ways, although not completely.
Took a Level in Kindness
Undying Loyalty: Towards the Alliance, usually to an unreasonable and hypocritical degree. This makes working with Cerberus, and being accused by Kaidan of being a traitor to the Alliance, that much harder.
Unknown Relative: Is unaware of the existence of her younger half brother.
Unresolved Sexual Tension: With Liara, before and after their romance. A mostly one-sided version with Kaidan, who seems to maintain a small flame for Beatrix throughout the trilogy (Beatrix feels some physical attraction to Kaidan, but it never becomes a crush.)
Violently Protective Girlfriend: To Liara (also see Violently Protective Ex-Girlfriend), although it comes through with Garrus to a lesser extent.
Vitriolic Best Buds: Possibly with Wrex. The two are very similar in the way they approach the world but a lot of these similarities mean they clash: both are stubborn, hot-headed and trigger-happy, although Wrex's wisdom and less controlling personality keep the two from being Too Much Alike. Could also be argued this is present in her relationship with Kaidan. Weapon of Choice: The Widow Sniper Rifle
What the Hell, Hero?: A lot of people towards her, including Beatrix herself, at various points.
ME1
- spared Rachni Queen
- spared half of Feros colonists
- found Wrex's armor
- Garrus pushed towards Spectres
- Wrex talked down on Virmire
- sacrificed Ashley
- sacrificed Council
- BDtS: sacrificed hostages, Balak dead
ME2
- saved Sidonis
- destroyed Maelon's data
- destroyed heretics
- Tali loyal, not exiled
- killed Morinth
- squad 99% loyal
- saved all of crew
- Suicide Mission 99% survival (Zaeed dead)
- destroyed Collector Base
- OL: saved David Archer
ME3
- cured the genophage, did not reveal sabotage
- Kaidan talked down on Citadel
- killed the Rachni
- brokered peace between Quarians and Geth
- Jack, Jacob, Samara alive
- Miranda, Cortez dead
- Omega: let Aria kill Petrovsky
- Citadel: killed clone and Brooks
- Destroy ending