For examples in the other games in the series, go here.
The Subspace Emissary
- At the very beginning of Subspace Emissary, Mario and Kirby are performing a friendly fight while Princesses Peach and Zelda watch. Regardless of who wins, the match ends with the two contenders shaking hands and smiling and being good sports. It's kind of sweet to know that they're both okay and that they have so much respect for each other.
- Things go downhill immediately after this, with the baddies beginning their campaign of terror. Petey Pirahna grabs the princesses and throws them into cages, and as the fighting continues, Kirby realizes that things are about to go straight to hell. He has the ability to get himself the hell out of Dodge, but makes a point of taking one of the princesses with him—it's like he's determined to save someone, even if he can only save one person.
- The confrontation between Bowser and Donkey Kong; Bowser has a gun that transforms the characters intro trophies. Diddy Kong doesn't understand the danger he's in, so Donkey Kong performs a Heroic Sacrifice by knocking Diddy into the air, Taking the Bullet meant for Diddy. He gets himself transformed into a trophy, all to protect his buddy. Aw!
- The friendship that forms between Samus and Pikachu is sweet. Samus is the "I Work Alone" type; and since she's human and Pikachu is a Pokémon, it makes her look like Pikachu's trainer.
- Especially her face when she sees Pikachu being basically tortured in the machine. She takes in about a second of seeing the little guy squealing in pain and promptly responds with a non-verbal Big "NO!" and smashes the glass.
- And what does Pikachu do the second it's released from being tortured? Jumps in front of Samus with cheeks sparking, ready to defend its savior from the R.O.B.s attracted by the alarm.
- When Ness realizes the badges that revived him and Luigi belong to Dedede, he immediately decides to revive him. This for some guy he doesn't even know. On that note, there's also that moment before the heroes enter the Subspace Labyrinth, where Ness and Luigi helping Dedede up after Wario attacks him.
- Ness gets another when he jumps in to save a kid he just met. Then he pushes him out of harm's way, not knowing if he'll be revived or not! Ness is a real sweet kid. And years later, when Nintendo wanted to show Lucas' return to Smash Bros, what did his reveal trailer depict? Lucas coming to Ness' rescue, repaying a long overdue favor.
- Whichever scene you play ("Mario's Misunderstanding/Link's Misunderstanding") is kind of heartwarming in a way. Which of the two scenes plays out depends on which princess gets rescued by Kirby in the scenario mentioned above; the hero of the one he doesn't save is the one who has the misunderstanding. If it's Mario, he thinks that Peach has been attacked by Link, and rushes to avenge her. If it's Link, he thinks that Mario attacked Zelda, and tries to ram his sword down the plumber's head. Either way, it's nice to know how much they both care.
- Dedede! Boy, was he a surprise! First, he gathers up as many heroes as he can in one place to make a hero team. Then he gives up the one thing he knows can revive trophies for one of the princesses. Near the end of the game, he gives Kirby a Bear Hug.
- The friendship between Pokémon Trainer and Lucas, particularly their handshake after Lucas blows up Galleom's arm to save himself and PT. And Meta Knight swooping in and saving the duo from a deadly fall at the last minute, after Lucas frees them from Galleom.
- After defeating Tabuu, you see the entire playable cast (or at least, all those you saved) on a cliff, overlooking the ocean where the Great Maze area of Subspace was, with the main theme blaring full blast. Then, the credits cut in, with an epic medley of the credits theme of the original Smash Bros., the main theme of Melee, and a piano solo of the main theme from Brawl, all while bits of cutscenes that correspond to the mood of the music play in a little box on the screen.
"Now, my friends are here with me.
- The music is great, and now knowing the lyrics, its meaning is clear.
Some once heroes, some my mortal enemies.
And now, as we face each other in battle, locked in combat,
we shine ever brighter."
- The fact Diddy Kong forces Fox and Falco to help save his friend Donkey Kong is sweet. For Donkey Kong, at least.
- The fact that neither of them even protest much indicates that they really don't mind helping. Falco's thumbs-up to Diddy is proof of that.
- The second time around with Diddy dragging Falco, Fox follows behind giving Falco a "Just roll with it" expression that really helps to drive home that he (and Falco) are absolutely cool with helping the guy out.
- When we first see Yoshi, he's napping peacefully in a quiet forest.
- When Snake finally joins the party, he doesn't seem to know exactly what's happening, but he knows enough to know that he needs to lend a hand. First, though, his priority is to urge Peach and Zelda to stay where they are, so that they remain out of harm's way. They don't, of course, but considering that he's just met them both for the first time, it's very good of him to want to make sure they're safe. (And to be fair, it's not like he knows one of them's a freakin' ninja.)
- Peach stops a fight between Sheik and Fox...by offering them tea. It's both a CMOH and a CMOF, especially when Fox glances at Sheik and sees her drinking tea through her face wrappings.
- When Link and Zelda find Ganondorf's trophy, they share a glance with each other before reviving him. Ganondorf is shocked by this, and while he considers attacking them the moment they turn their backs on him, he decides against it and instead follows them to fight Tabuu, knowing that the Subspace entity is the true enemy.
- Diddy Kong urging R.O.B. to escape before the area they're in explodes, and Donkey Kong just straight up carrying R.O.B. out when he refuses to move.
- Like the Mario and Kirby fight before, Lucario and Meta Knight shakes hands and join forces after their fight.
- The Ice Climbers are delighted when Lucario and Meta Knight make peace.
- The concept alone of the many famous protagonists of several video game franchises teaming up together to defeat one great evil. Even better that even the antagonists, who were initially puppets of Tabuu, join our heroes in the very end to save the world, knowing that it's for the greater good.
Other modes and the overall game
- The reason behind Hideo Kojima asking Snake to be in Brawl? His kids are fans and they wanted to see one of their father's characters in the game. Kojima had also requested for Snake to be in Melee, but due to time constraints, his debut was put on hold until Brawl.
- During Snake's codec conversation about Luigi, Snake instantly argues in Luigi's defense when AI Colonel starts mocking Luigi.
- Another codec conversation, Snake sympathizing with Lucas' troubles and with the loss of a brother and mother is particularly heartwarming.
- In the codec conversation about Falco, Snake is actually rather friendly towards Slippy after the latter hacks his communicator to talk to him. After complimenting his weaponsmithing skills, which flatters Slippy, he expresses interest in having Slippy design something for him.
- After defeating Wario in the Subspace Emissary, Lucas and the Pokemon Trainer high-five each other. Lucas becomes sad when he remembers what happened to Ness, but the Trainer gives him a reassuring pat on the back. That was pretty cute.
- When the Pokemon Trainer wins a match, one victory pose for each of his Pokemon has him showing affection for them in some way, or them showing him affection. Squirtle bashfully rubs its head as the Trainer hugs it, Ivysaur glomps him and he hugs it back, rubbing its chin and patting its head, and with Charizard he hugs it before turning to the camera, leaving one arm around the back of its head. They're all pretty cute, especially Ivysaur's, and it demonstrates the Trainer cares for his team.
- The Nintendog hopping up to the screen and pawing at it is probably the cutest thing in the games. Even if it disrupts the fight.
- In a meta sense, Pit's relationship with Brawl. He was included despite not being too well-known, and was given a complete redesign as part of his inclusion. His new design, general attitude and role in The Subspace Emissary made him a quick fan favourite, leading to him getting a new game after years of being neglected. In other words, Brawl gave Pit and his series a second chance.