- Joey and Mai are quite cordial to each other in contrast to the usual trash talking they and most other duelists invoke towards others, and Joey still being the Butt-Monkey of the game. Considering how tumultuous their relationship was in the series, especially the anime, it's nice to see that everything worked out in the end.Mai: Joey, I may have lost, but I had a blast!
- During the first Duelist Challenge event, Joey and Rex bonded over finally having something in common.
- Ishizu and Odion's interactions with Yami Marik, while sad, are also heartwarming as they vow to bring back the real Marik.
- Losing to Yugi with Yami Yugi leads to the former giving a sweet Call-Back to the end of the original series.Yugi Muto: I'll never forget you, my friend.
- If Mokuba defeats Seto, Seto refuses to make excuses and acknowledges his brother's strength.
- Rex's Dino Mayhem event was all about him celebrating dinosaurs, and he decided to let Joey keep his Red-Eyes even though it originally belonged to him.
- If Chazz attacks with Ojama Yellow, he'll admit that it really is his ace monster. A callback to his duel against Aster where Ojama Yellow finishes Aster off.
- Chazz dueling or defeating Alexis results in adorable Ship Tease.
- Have Zane duel Crowler, and Crowler's first and foremost concerns are about Zane's health regarding his heart.
- Bonz's Spooky Party event had a misunderstanding about Bella losing her card and Joey thinking he stole it. Between that, being depressed over his face scaring everyone, and being scared of Bandit Keith, he decided not to come back to Duel Links anymore and gave Bella his Pumpking after returning her card. But Bella asked him to duel her, Joey apologized for the mistake and offered to duel him a bazillion times to make up for it, and Yami Yugi vowed to duel him as well, cheering Bonz up and making him stay. What really seals the deal is the card Bella lost was Shining Friendship, which reappears after the dialogue to symbolize their newfound friendship.
- Unlock Bonz and he'll tell you he's not into actual horror like Keith or Bakura, but more into friendly horror, hoping to master the Ghostrick deck because he only wishes to use horror as a means of having fun with people.
- Despite the Hell Kaiser persona, Zane isn't completely changed. He is happy to see Jaden (well, as happy as a Blood Knight gets), knowing Jaden can give him the duel he desires, and if you beat him, he'll say that Jaden will be the best at the academy. Jaden and Alexis also vow to turn him back to normal when dueling him.
- The third Duelist Challenges event has some nice moments between Ishizu and Odion.
- If Syrus defeats Zane, he'll straight up drop the Hell Kaiser act and be legitimately proud of his brother for surpassing him (a nod to season 4). Lose to him, and while Zane will still act like an asshat, Syrus will still have a love for his brother and hope he'll still remember the duelist he was and one that Syrus looked up to.
- If you lose to Tristan as Yugi, Tristan will show genuine concern for his friend and ask if he's feeling well.
- Of all characters, Yami Marik has several moments where he's kind to Arkana, complimenting his skills during his Ra event and offering to make him second-in-command if you duel him as Arkana. If you win, he praises his skills and hopes he continues to serve him faithfully.
- In Yubel's event, several characters try to protect Jaden from her, including Jesse and Dr. Crowler. Alexis is also deeply concerned about him always having to save everyone, vowing to defeat Yubel for him on her own.
- A fitting Call-Back to season 3's conclusion: Should Jaden defeat Yubel, Jaden will help Yubel find the right path again, which was one of the last things he said to her before their fusion.
- Upon unlocking the 5D's world, we are introduced to Jack challenging Yusei to a duel to claim the title of Duel King, except Jack refuses to challenge Yusei. This seems uncharacteristic of him but he then points out that the deck Yusei has in Duel Links isn't his. But Jack knows that Yusei will be able to turn this deck full of random cards into something spectacular and they will get their epic rematch soon as both looks forward to continuing their rivalry in the world of Duel Links
- When dueling against Jaden or Yugi as Yusei, Yusei's dialogue serves as a Call-Back to Bonds Beyond Time and how the two helped Yusei out in the last Duel of the movie. The Japanese version of the dialogue even has Yusei refer to them as "Judai-san" and "Yugi-san."
- Luna's unlocking speech has Ancient Fairy Dragon reassure her that her kindness and heart is what makes her strong, and she should duel with her friends and believe in herself.Ancient Fairy Dragon: Be strong, Luna. Be true to yourself. So that you can walk alongside - not behind - your companions.
Luna: I... I do want to be here! To play and learn from my friends! We may go our separate ways someday, but I don't want that time to be now!
- For both Luna and Leo, the twins each use their sibling's synchro chant when they use the other's dragon.
- There's a tribute to one of Akiza's signature scenes, the WRGP duel against Team Unicorn, where she summons Stardust Dragon. Her characterization in general is heartwarming to see, as she wishes to become a strong duelist like Yusei and Jack and has put her past behind her.Akiza: Take flight, Stardust Dragon! Yusei... With your power by my side, I have nothing to fear!
- As a shout-out to his duel against Z-ONE, Yusei will not only say the summoning chants of all of the Signer Dragons (even Leo's Power Tool Dragon), but he also says the names of their attacks and special abilities as well as if he was their normal user.Yusei: My friend's very soul, Red Dragon Archfiend!
- The second Monster World campaign revealed Tristan took on Yami Bakura to save Ryou Bakura, and when he has to be recused, Tristan implores the player to teach him how to duel so he can help his friends more. If you duel Yugi as Tristan, he encourages him win or lose and is overjoyed to see him taking up dueling.
- The Stardust Cup has Ojou Chloe tell Liam he should be grateful that a Topsider is teaming up with him. When they lose, Liam apologizes for being from Satellite, and Chloe tells him that where they're from has nothing to do with Dueling and the only ones to blame are the team that beat them.
- When you lose against Jack Atlas, unlike most characters, and unlike what his usual personality would imply, Jack actually gives encouragement so that you don't give up, and try harder. It implies he does have some level of care towards his opponent.
- In his unlocking event, if you duel Tyranno Hassleberry as Jesse Anderson, Hassleberry wants to watch Jesse's Crystal Beasts in action so he can form a stronger bond with his dinosaur cards. Jesse agrees to duel him, but notes he already has a strong bond with his monsters, which delights him.
- Should Lumis & Umbra win a Duel, and for all their bickering, the latter will sometimes have this to say.Umbra: You've proven once again why you are the best partner ever!
- Additionally, should they lose a Duel, Umbra might start coughing, while Lumis worriedly asks if he's okay.
- In the 4th Tag Duel Tournament event, Yugi and Tea are partnered together. Once they lose, Yugi says that they wouldve won if the Pharaoh was partnered with her. Teas response? Tell him to never say that again, showing that Yugi is the only partner she wants.
- During the Hassleberry Unlock Event, when Hassleberry freaks out and starts to be overcome by his dinosaur side, the GX cast just shrugs and decides they'll help him snap out of it. Even Chazz and Aster. True Companions indeed.
- During Kalins event, Akiza actually sees where hes coming from in being ostracised by his peers, having gone through a similar experience herself.
Heartwarming / Yu-Gi-Oh! Duel Links