- While we never see Cipher's reaction to his trusted wingman Pixy's betrayal in Ace Combat Zero: The Belkan War, many players were emotionally shaken by it.
- ANNO: Mutationem: C expresses outrage after seeing G, B, and K have chosen to turn against him after his machinations have gotten out of control and that he needs to be stopped.
- Villainous example in Apollo Justice: Ace Attorney in the very first case, no less! When Apollo turns against Kristoph Gavin, who at the time is his boss and mentor, Kristoph says this to him almost word for word.
- A double-whammy in Arc the Lad: Twilight of the Spirits: Darc forms an alliance with Delma and her power-hungry brother Densimo. When his father's killers arrive, they give Densimo a furble, which he can eat to expand his power. Densimo takes the offering without hesitation. Darc is also betrayed by his master Geedo, who treated him like crap but he still loved her for caring for him. When he realized how little he meant to both, he went off the deep end and killed both of them as well as the murderers, and vowed to become king of the Deimos.
- Assassin's Creed:
- Connor from Assassin's Creed III is none too pleased when he finds out George Washington is the culprit in the burning of his village, and also the fact that his father Haytham has been hiding this information from him that he cuts his ties with them both.
- At the midpoint of Assassin's Creed Origins, this hits Bayek and Aya as Cleopatra, who they just helped take the crown from her brother Ptolemy, has betrayed them by allowing Lucius Septimus, one of the Order of the Ancients to remain at her side, ousting Bayek and Aya from her court. The trope namer is played straight at the end of the game with the Ides of March, starting with Aya getting the first stab into Caesar.
- In Assassin's Creed: Revelations, Altair's younger son Sef was killed in the coup that occurred while Altair was away. The assassin who stabbed Sef to death twisted the (figurative) knife by claiming that he was being killed on Altair's orders.
- In Baldur's Gate 2, one of the two events that every NPC party member will have an interjection about (the other being when you face down the Final Boss) is if you bring The Mole with you to Spellhold where they betray the party. Some party members will take it harder than others, with reactions ranging from a refusal to believe it to grim resignation, but practically all of the non-Evil party members will clearly be upset about it (except Haer'Dalis, who finds the betrayal to be a great twist).
- In Bionic Heart, the protagonist ends up hiding a fugitive android in his apartment because she needs his help in her ontological quest. If the main character chooses to confide in his best friend and coworker Tom, Tom ends up giving up both the protagonist and the android to the police, which leaves them in the hands of the corrupt corporate executives that were pursuing the android in the first place.
- In Black Mesa, the scientists can quote this verbatim if you attack them. After all, the only thing worse than being trapped in a facility filled with murderous aliens and military death squads is the knight in powered armor that's supposed to protect you from them suddenly turning against you.
- You can elicit this reaction if you decide to go for the bad ending of The Caligula Effect: Overdose. The game allows you to both lead the good guys while joining the villain team in disguise, and the bad ending has the player character reveal the ruse right before siding with the Big Bad. Your party members, all of whom looked up to you, are understandably horrified, enraged, and heartbroken, and you get treated to one hell of a series of reason you suck speeches as you fight your way through them all.
- Celestian Tales: Old North: After Alain reveals that the new Levant heir is Sophia's unborn child, Severin angrily attacks him, stating that because Alain is infertile, not Sophia as widely believed, he couldn't possibly be the child's father, and therefore the child is not a legitimate heir.
- Devil May Cry:
- Dante in Devil May Cry is hired by Trish to look for Mundus on an island. This is because she's working for him. When Dante finds that out, he is not happy about this. He and Trish finally make up in the end, anyway.
- In DmC: Devil May Cry, Dante has been working closely with Kat and Vergil to aid "The Order" to overthrow the hold the demons have on the world at Mundus's control. Then after Mundus falls, Vergil reveals that his efforts were working to remove Mundus from power and seat himself and Dante as rulers of humanity going forward. Dante is shocked by this and refuses to accept Vergil's outcome, leading the brothers to fight to the death.
- Fenris of Dragon Age II is a former Tevinter slave on the run from his master, Denarius, who is... not a nice man. He catches up to Fenris in the last third of the game, while Fenris is in Hawke's company, and Hawke has the option of fighting him off — or giving Fenris back to him. Fenris hits this reaction hard, especially if he and Hawke are friends, and especially if he's in a romance.
- Hawke will certainly feel this trope when Anders lied to them about the purpose of his last companion quest which is to blow up the Chantry in order to incite mage rebellion that spread across Thedas. This is cemented when they decide not to support Anders and executes him right on the spot. Even when they discredit Anders' actions at the climax of the game and is simply an unwitting accomplice in his plans, Hawke still ends up becoming a fugitive because of this.
- In Dragon Age: Inquisition's Trespasser DLC, there is a chance of this happening. If you did Iron Bull's quest and made him pick the Qunari over his friends, he will betray you and your group and become hostile during a fight with some Qunari. Since this happens late in the final DLC of the game and the deciding quest happens early on in the base game, you may have spent many hours with him in your party and probably forgot all about your choice. Made even more devastating if you have Dorian, his romantic partner, with you as well.
- Dragon Quest IV: Hank Hoffman's best friend turned on him while searching Casabranca/Branca Cave. At least, that's what it seemed like at the time...
- The Elder Scrolls:
- In Morrowind's backstory, one of the conflicting accounts of the final days of Lord Indoril Nerevar states that he was betrayed and murdered by his three trusted councilors, known as the Tribunal, after they became obsessed with the potential powered offered by the Heart of Lorkhan. According to this account, they each poisoned Nerevar in a different way as he meditated to commune with his Daedric patron, Azura. The Tribunal then tapped into the power of the Heart in order to become gods. During the game, in conflict with the Tribunal Temple's official story, Vivec will admit that he betrayed Nerevar. In one of his writings, hidden in metaphor, he states that he (as the mortal Vehk) did in fact murder Nerevar.
- Skyrim:
- The Ebony Blade is a unique two-handed katana with a Life Drain enchantment that increases in power when you use it to kill characters who consider you a trusted friend, reaching its full power after 10 kills.
- Jarl Balgruuf will chew you out if you side with the Stormcloaks and sack Whiterun.
- Fallout: New Vegas: Mr. House essentially invokes this if you kill him. Caesar as well if you had sided with him and then kill him in the aptly-named quest "Et Tumor, Brute?" Dr. Klein says this to Dr. 8 in Old World Blues if you get him to side with you in the final battle.
- Tohsaka to Archer in Fate/stay night's Unlimited Blade Works route. After keeping calm throughout the story, she's devastated and doesn't hide it terribly well when he betrays her twice. On the plus side, the event is a catalyst for her Relationship Upgrade with Shirou. It's also a real bonding experience for her with Lancer. Hell, this is the only reason Saber exists. Although she fought virtually the entire world as King of England, and never lost a single battle for 12 years, she died at the hands of her own trusted men and specifically by the hands of her "son" Mordred, though Mordred likely saw it as answering a betrayal of her own for shunning her true identity. As well as Archer, who ended up getting betrayed and killed by the very people he dedicated his life to protect.
- Final Fantasy:
- An Easter Egg of this exists in Final Fantasy X. The Aeon Anima, Seymour's personal Aeon, is the spirit of Seymour Guado's mother. If you summon Anima in the final battle against Seymour (the only Seymour battle you can have her for), he doesn't take it well:
"You would oppose me as well?!? So be it!"- In Final Fantasy XIII, Sazh had no problem fighting with Vanille against PSICOM until he realized that Vanille was the reason his son became a l'Cie he was about to kill her and commit suicide. He fortunately came back to his senses.
- In the Fire Emblem series:
- In Fire Emblem Fates, the unfortunate protagonist will be getting this from someone since they have to decide between siding with their birth family or their adoptive family in a war. Taking a Third Option means getting this from nearly everyone, though they do eventually get their siblings on both sides to join them.
- In Fire Emblem Echoes: Shadows of Valentia, Berkut takes it very, very badly when he finds out that Rudolf had been lying to him for his entire life and that he never actually had a chance of becoming emperor of Rigel, a goal he had worked his whole life for. It ultimately becomes a deconstruction when Berkut actually goes insane due to the betrayal and proceeds to sacrifice his fiancee to the local Mad God in exchange for the power to earn what he was always led to believe was rightfully his.
- Fire Emblem: Three Houses has plenty to go around after Edelgard is revealed to be the Big Bad Flame Emperor.
- Edelgard's stepbrother and childhood friend Dimitri goes completely berserk when he discovers the truth, as he has come to believe that they orchestrated the Tragedy of Duscur that resulted in the deaths of all of his family and many of his knights. He becomes completely obsessed with ripping their head off from that point forward.
- On the Silver Snow route, Byleth doesn't take the betrayal very well at all and remains with the Church of Seiros to bring them down even if it means fighting the house leader they've fought alongside and taught for nearly a year.
- On the Crimson Flower route, Byleth defects to her side and takes nearly the entire Black Eagles class with them. This leads to Rhea, Seteth, and Catherine denouncing you as a traitor, and depending on who you have and haven't recruited you can easily destroy several friendships this way.
- Villainous example in Galaxy Angel: Moonlit Lovers. In Chapter 4, Nefuria suddenly backstabs Rezon Mayzon by attacking his ship, revealing that she'd just been playing him all along. Then she remotely takes control of his ship, sending it in a collision course against the elsior before activating a self-destruct mechanism, killing him in an explosion. Even the Elsior's crew is outraged by this.
- Grand Theft Auto: San Andreas: CJ is pretty hurt when he finds out his best friends Ryder and Big Smoke had been working with the Ballas. A few seconds later it's revealed that they arranged the hit on his brother that took their mother's life.
- Halo: The Arbiter fought for the Covenant against humanity with no problem at all, but when the Prophets (who had given him a second chance by making him the Arbiter to begin) betray him and the entire rest of his species (with the Arbiter himself betrayed by the Prophets' main enforcer Tartarus), the Arbiter is forced to ally with humanity and lead a rebellion against the Covenant.
- In inFAMOUS, Cole is incredulous when Zeke attempts to activate the Ray Sphere a second time, which would further devastate Empire City because Zeke really wanted superpowers. Even after the "asshole makes the choice to kill thousands," in Cole's words, it doesn't do anything because Zeke's not a Conduit. Even so, Cole is so stunned by Zeke's betrayal that he hardly notices when a tower collapses right on top of him.
- Katawa Shoujo: when Hisao is forcefully woken up by Shizune and Misha, this trope is humorously invoked.
- Cole Phelps in L.A. Noire has no problem working with Roy Earle, despite the fact they don't like each other until he discovers he's the one who reported his affair with Elsa Lichtmann to the corrupt officials.
- The Legend of Heroes: Trails:
- The Legend of Heroes: Trails from Zero and Trails to Azure: Having considered Dieter and Mariabell as a father figure and her best friend respectively, Elie is quite hurt by the reveal of them being Evil All Along.
- The Legend of Heroes: Trails of Cold Steel: Jusis was absolutely shocked to discover that his older brother Rufus, who had been the one who instilled the values of nobility into him, was secretly the right-hand man of Osborne who sought to abolish the nobility.
- The Mass Effect series has plenty of examples, beginning with the second death in the series: Sacrificial Lion Nihlus is shot in the back of the head by his old colleague Saren.
- Garrus's whole loyalty mission is entirely focused on him finding and dealing with someone who did this to him. After Shepard recruits him, he tells him about a traitor named Sidonis who sold out his squad to the various merc groups on Omega and told them where the squad were hiding, causing the mercs to track them down and kill everyone but Garrus. You find out later that this wasn't quite the case, as the mercs actually threatened him at gunpoint for the location of the base, and he feels very guilty for actually giving in to their demands. While Garrus at first still wants to execute him for being a coward, you can convince him to back down.
- This also happened to Zaeed Massani, courtesy of Vido Santiago. He and Vido founded the Blue Suns mercenary group as a business venture over twenty years ago. While mercenary groups aren't exactly known for being morally scrupulous, Zaeed tried to keep the Blue Suns fairly clean. Vido, objecting to this because it cut profits, turned Zaeed's men against him. He paid a group of them to hold him down while he shot Zaeed in the head (Zaeed survived).
- Shepard has a Heroic BSoD when the Council pulls them off the hunt for Saren. For a Paragon Shepard, this comes as a real blow.
- Shepard themself can do this in Mass Effect 3 for various reasons. A particularly bloodthirsty player can personally kill four close friends — Mordin, Wrex, Legion, and the Virmire Survivor — in a single playthrough.
- Master Detective Archives: Rain Code: Two moments in the game show Halara might be more sensitive to betrayal than any other experience, due to their past experiences. The first is when Halara hears Shinigami refer to them as "Hellara" while in the Mystery Labyrinth, seemingly aware the nickname is intended to demonize them due to their blatant Greed; the reason for this reaction becomes clear in Gumshoe Gab, as the money Halara is saving through their detective work is supposed to be for a charity for cats. The second is during the Gumshoe Gab itself when Halara sounds as though they're on the verge of tears when they thought Yuma had tricked them into revealing they were looking at cat photos in the alley. Of course, Yuma quickly corrects himself in this moment, saying that he was basing it off previous observations of Halara.
- Happens in Mega Man X7's prologue, when Axl and Red Alert were infiltrating the base of a maverick. His second-in-command seemingly finds him, and then while leading him away, he shot the guy in the back. However, in this case, it was a subversion, as the actual second in command had actually been killed earlier by Axl, and the "second in command" who shot his boss was actually Axl.
- In Metroid: Other M, the event that triggered MB's rampage aboard the Bottle Ship was her "mother" Madeline Bergman doing nothing when security showed up and dragged her away to be given the AI equivalent of a lobotomy.
- In Mirror's Edge, Faith briefly
has this reaction when she finds out that Celeste has joined the other side. - In NEO: The World Ends with You, Shoka, one of the Shinjuku Reapers, gets kicked out at the end of the second week and joins up with the Wicked Twisters(i.e. the party). At the end of that day, it turns out that Shoka passed along information about Rindo's time reversal powers to Shiba in order to rejoin the Reaprs, and Rindo is outraged at Shoka's betrayal. However, Shoka, overwhelmed by guilt and refusing to see Shibuya be destroyed, refuses to rejoin the Reapers and permanently joins the Wicked Twisters, who are able to forgive her.
- Neverwinter Nights: Everyone's reaction (possibly including the player) to Aribeth's Face–Heel Turn.
- A2 from NieR: Automata is named after Julius Caesar's last words, hinting at her betrayal of/by YorHa.
- Prayer of the Faithless:
- When Aeyr becomes a Revenant, Amalie turns on him because she believes Revenants are mindless monsters, ruining the trust Aeyr had in her and causing him to believe that if the world is going to see him as evil, then he should no longer care how he treats anyone outside of his circle of friends. At this point, he's willing to run roughshod over civilization in order to protect his best friend, Mia, at any cost. After taking over Asala, Mia sends Aeyr to Purgatory to kill Gauron but omits that if he succeeds, he'll die without his Revenant-induced Miasma immunity. When Gauron reveals this to Aeyr, the latter spares Gauron, makes the Fog traversable to normal humans, and sends a letter challenging Mia to confront him in Purgatory.
- When Mia's party discovers Vanessa's Infused experiments in Lavingard, Vanessa orders Amalie to kill the rest of the party. When Amalie fails, Vanessa abandons Amalie and labels her a fugitive along with the rest of them. This causes Amalie to fall into despair since she considered Vanessa to be her savior in her time of need. Although Mia convinces Amalie to fight to save the people of Asala from Vanessa, it's possible for Mia to betray Amalie's hopes in the Love ending, where Mia gives up on saving Asala, causing Amalie to join the rest of the party in attacking Mia.
- In Saints Row 2, it was revealed that Julius tried to kill The Boss by destroying the yacht seen in the finale. The Boss had Julius as their boss before he became the Saints' leader.
- Depending on the path you choose throughout the game, this is the usual response from the heroes whenever you take the villainous path in Shadow the Hedgehog.
- In StarCraft, there tend to be a lot of instances of people betraying others. In StarCraft II, Tychus reveals that he was given an order to kill the newly de-infected Kerrigan, regardless of the fact that she's no longer zerg, and as a result, Raynor has to kill him.
- SLAMMED!: This happens twice:
- First, JJ betrays you by getting you fired from the GWA by having Griss/Giana plant an illegal drug in your bag, and sabotaging a mandatory drug test to motivate the promoters to search your bag.
- Second, in the Ladders and Scaffolds match with you, JJ, Solitary, and Super Horns vs. Paul Prototype and his Lawgivers, just as Solitary is about to grab the belt, Super Horns betrays him by pushing him off the scaffold.
- A running theme throughout the Suikoden series is the main hero having to deal with the betrayal of a close friend or ally — which he usually has the option of forgiving. (Doing so helps determine what ending the game gets.)
- The first major blow in the Break the Haughty act played on Luke in Tales of the Abyss is his mentor Van betraying him and leaving him for dead.
- Tales of Destiny: Stahn gets pretty upset when Leon betrays the party. So do the others, to lesser extents. But Philia took it worst of all, as shown in the sequel when she talks about him. Later, Ilene sides with Hugo rather than Stahn and commits suicide. Stahn goes into a full-out Heroic BSoD.
- In Warcraft III, King Terenas Menethil reacts appropriately with shocked horror when he realizes that his son Arthas, who has just returned from a seemingly successful campaign to eliminate the Scourge, is not here to give his father his regards.
- Wild ARMs: Million Memories:
- Filgaia goes up in a ball of fire after the heroes fail to stop the demons' plans, because Rudy (yes, that Rudy) betrays everyone. Your party is understandably upset and confused by this turn of events but cannot seem to do anything about it. This is all revealed in the opening cutscene with the context not being revealed until the very end.
- Related to, and hidden by the above Mother is equally confused when Siegfried chooses to fight alongside Rudy to protect Filgaia, instead of destroying the world on her behalf.
- Two noteworthy examples from Xenoblade Chronicles 1. Dunban is utterly appalled with his old war buddy Mumkhar betraying his entire species. Though in this case Mumkhar never really liked Dunban while Dunban always considered him a friend and didn't notice the jealousy Mumkhar harbored for him. The second example would be Dunban and the whole gang being horrified to learn that Dickson, Dunban's second old war buddy and a father figure to Shulk was deceiving them the whole time and plans to kill them all.
- The third example is Egil's belief that Mayneth has betrayed him. Egil is disappointed the remaining members of his species are against his genocidal plans but when the god he knows personally tries to stop them he downright almost cries. His behavior clearly brings great pain to Mayneth too. Terrific voice acting really hammers home how personal the betrayal feels. Also a bit of an odd case since the hero character is the one being accused of betrayal.
