Heartwarming: Super Mario Bros.

  • Bowser of all characters gets one in Super Mario Sunshine when Bowser Junior reveals that he knew the whole time that Peach wasn't really his mother, but he still wants to follow in Bowser's footsteps. It was just sweet to see some father/son bonding, even if it is between two evil turtle-dragons.
  • The end of Luigi's Mansion. Mario is turned back to normal after his painting is rescued by Luigi. He humorously crashes through the machine that turned him back to normal's opening. Luigi cries from both the relief that Mario is finally safe, and from laughing so hard at the vent stuck around Mario's head.
  • The first time you rescue Princess Peach in Super Mario Bros.
  • Though it's not a part of the games, this tribute made for Mario's 30th Anniversary is likely the most beautiful celebration of Mario's history out there. According to the description, it was a joint effort between fans and the creators of the Mario games, making it even more heartwarming.
    Congratulations Mario! You accomplished the 30 years of work. But your adventure isn't over yet. So, let's go to the next stage now!
  • The ending of the original Mario vs. Donkey Kong for GBA after defeating the True Final Boss: Donkey Kong breaks down crying, having failed to keep the Mini-Mario toys he had stolen from the toy factory. Mario, seeing this, takes pity on the big ape, and comforts him, even giving him a Mini-Mario toy to call his own.
    • And beforehand, there's the first part of the opening scene. Even though it marks where things start going wrong, seeing Donkey Kong falling in love with the Mini-Mario Toys he sees on the TV is very uplifting. It makes sense when you consider that the newer Donkey Kong, the offspring of the original (known as Cranky Kong), is shown to be one of Mario's friends!
  • It is very minor, but in one of the character pictures for Mario Golf: Toadstool Tour shows Wario and Waluigi practicing golf. Now, as we have seen in the trailer, Waluigi seems to be a very poor golfer (probably because it's his first time), and the picture shows him ready to strike the ball. But, you actually see Wario, being far more experienced, teaching Waluigi to golf properly by correcting his posture by using the chin-up method. It's very rare to see Wario caring for Waluigi and showing he isn't all about greed and power, even despite their constant bickering.
  • The scene where all the characters in Paper Mario: The Thousand-Year Door are sending you hope and support to defeat the Shadow Queen is definitely heartwarming in itself. See it here.
    • YOU GO BRO!
  • In Super Mario RPG, you can read the wishes of people. Two are particularly sweet.
    Please let Mallow find his way home.
    I wanna be a great plumber like my brother Mario.
    • You know what's sweeter? They both came true.
  • The movie has the scene where Luigi and Daisy say goodbye.