* The death of E-102 "Gamma" at the end of his story in ''Sonic Adventure.'' Though what really makes it is [[http://www.youtube.com/watch?v=9-9FaXg5NOk the music]].
** Gamma's death isn't all that sad, upon considering that [[spoiler:the bird inside is finally free to be with its family]]. Although that's definitely touching.
*** It depends how you view Gamma's consciousness, [[AlternateCharacterInterpretation is it composed of the brainwashed bird inside a lifeless robotic shell, or is it a sentient life sacrificing his new-found life for the sake of the being powering him?]] This comes off as even more powerful in the ''SonicX'' version, where Amy bares witness to his HeroicSacrifice. While happy that Lily is reunited with her liberated parents, after they flutter away, she immediately bursts into tears over the now decomposed robot shell on the ground (made EVEN MORE powerful in the formation Beta and Gamma have fallen, their hands collapsing on each other as if to represent unity).
---> '''Amy:''' You managed to free them. Thank you. We are friends from now on. Now you and your brother can live together again.
*** The prison cutscene. The supposedly intimidating robot confronts Amy for the bird, after she refuses, and in desperation, actually begs him to let it go. Gamma starts feeling pain from his new found empathy, going berserk before letting them out of their cell and ordering them to escape. He slumps over the door switch, dumbfounded and guilt ridden at disobeying his master's orders, though Amy shows sympathy and offers him her friendship before leaving. Gamma's heartwrenching theme playing in the background helps none.
** Keep in mind, the E-100 units in Sonic Adventure were essentially ''siblings.'' Gamma was forced to kill the only people he ever cared for -- with the exception of Amy and his creator Eggman (who he probably saw has his ''father'') -- for the greater good of saving the birdies from a FateWorseThanDeath.
*** Actually, Gamma is only aware of the birdie inside of him and another of his siblings when he defeats E-102 Beta MkII and frees that birdie. On top of that, Gamma has seen with Beta that Robotnik wouldn't [[YouHaveOutlivedYourUsefulness give higher orders to the failures among his machines]]. Instead, Gamma faced his siblings (E-103 Delta, E-104 Epsilon, and E-105 Zeta) in order to [[DefeatMeansFriendship rescue them]] from their being little more than EliteMooks to Robotnik. Yet the mission is to "Destroy" the corresponding member of the E-series and the victory cutscenes shows their [[FamilyUnfriendlyDeath absolute death-by-explosion]]. This actually makes Gamma's play-through a larger tear-jerker because it depicts a childlike innocence concerning what death really is. And this innocence is only broken at the end when he is able to actually understand [[HeroicSacrifice the cost of doing the right thing]]. With bonus tear-jerker points if you [[AlternateCharacterInterpretation carry out the implication that his finally understanding what death is]] [[RedemptionEqualsDeath means that he has decided to join the rest of his family which he was responsible for killing]].
* Speaking of ''VideoGame/SonicAdventure'' music, ''[[http://www.youtube.com/watch?v=jPbtnGU30fE Sadness]]'' is truly ExactlyWhatItSaysOnTheTin.
* [[spoiler: Tikal's implied death.]]
* [[WoobieDestroyerOfWorlds Chaos.]] Once a peaceful soul who cared for Chao and befriended Tikal, Chaos eventually lost it after witnessing [[spoiler: Pachacamac invading and slaughtering the very creatures he tried to protect. Driven over the DespairEventHorizon, he sought vengeance on the very Echidnas that had caused the catastrophe.]] Then he's sealed inside the Master Emerald to prevent him from harming anybody else, which means he spends [[AndIMustScream 4000 years trapped in a cocoon of anguish and sorrow.]] Even Sonic sympathises with him.
-->'''Tikal:''' He must be sealed in the Master Emerald now.
-->'''Sonic:''' How can that help? It won't change how he feels inside will it? His heart will still remain in turmoil, and his anger just won't vanish! He'll just be trapped forever.