Reaching the maximum floor of your company and getting the final reward.
When kidnapped by her own father, Lisa instructs Cody to find bombs and blow up his tower.
Blowing up Dr. Disc's tower in the first game, floor by floor.
After Dr. Zero defeated Prince Tail's father, the King attacked him and left him for dead. Zero repaired his original body with cybernetics, and when he returns, he calls out Prince Tail for what the King did.
Dr. Zero's revenge on Tail Kingdom and Porombo Island. He confronts Prince Tail with the truth of his past—the King won the throne by cheating—and defeats Tail, becoming the Legend1. Zero uses his newfound power to take over the castle, its soldiers, and the entire island. When Tail then loses to Cody, Zero imprisons Princess Darcy in a mirror, strips the Prince of the Legend3 title, and has him hauled off by his own guards. His revenge is so complete that in the sequel, he solely focuses on killing Cody since he already got his revenge on the Royal Family.
Defeating Prince Tail's Draco robot, which is one of the hardest fights in the entire game.
Defeating Dr. Zero's Brute, which knows the game-breaking Alpha moves.
Defeating Hunter's Golden Sunny to free Darcy.
A lot of Cody's time travel shenanigans result in obtaining XStones from impossible places, like a sealed volcano or an alien.
Tataki: Miho's feelings for me are going away... It's all your fault! I don't know what you did, but it's thrown my world into turmoil... I can't live my life like this, so I'll believe in love until the end. I live only for Miho! How do you feel, darling? [Miho shakes her head] Tataki: ...b-but... you love me, right? Please, tell me... Miho: You never listen to me, Tataki! You don't let me speak for myself. You always talk about your problems, but never listen to me! I can't love a man who doesn't care about what I have to say... It's important to let your partner in a relationship know what you're thinking. But it's more important to listen to the other person and understand them. Girls want guys who are kind, and listen when they're talking. Tataki: ...I see. I can change, Miho! I'll do anything... Just say that you'll be with me forever! Miho: You don't get it, Tataki! You keep trying to force people to act like how you want them to... but the real world doesn't always go as we expect. You're only looking out for your own desires! Other people have dreams, too. If you really loved me, you'd stop being so childish about this. You're selfish, and never stop to consider what I might want... The world doesn't revolve around you, Tataki! Things won't work out if you think only of yourself. You're taking me for granted... I have feelings too, you know. [beat] Miho: If you love someone... ...want to protect them... You'll take your partner's concerns for your own, and do your best for them! Girls don't want a guy with a sense of humor... we just say that. We really want a man who is supportive! That's not you, Tataki! It seems like all you care about is... You. Do you actually love ME at all? Even if you say so, I don't believe you.
Saving Mr. Waffle's company and his source code, and taking down Mr. Gait.
Taking out the Battleship by making it explode—while you're inside it.