In the cinematic trailer, several characters are quick to defend their partner, even though the majority met only moments ago.
Upon seeing him for the first time, Harley wastes no time gushing about how cute she thinks Taz is and nicknames him "Slobber". Taz, for his part, seems to quite enjoy the affection.
As everyone gathers together at the end, Reindog goes up to and gives a couple affectionate licks to Finn, whom chuckles heartily in return.
The Iron Giant's Rage Mode is activated by a button prompt labeled "Protect Friends!" Even when he's becoming the thing that scares him most - a weapon - he's only doing it for the sake of others.
Win a match with Tom and Jerry and the two of them celebrate with milk and cheese — a nice reminder that they can be civil when not in their never-ending game of cat and mouse.
Should Velma get a point by beating Shaggy, Shaggy is shocked and absolutely happy for his friend's victory.
If you happen to play the game on your birthday, whichever character you selected will personally wish you a happy birthday.
Same thing happens should you play around the Christmas season, any character you will select will wish you a merry Christmas.
While most of the lines you get for clicking on a character in the matchmaking screen are repetitive lines of the character asking what's up or if you need them for anything, some of them can be surprisingly heartwarming. Special mention goes to this one from Shaggy:
Shaggy: Like, man, I was just thinking... like I don't feel nearly as scared of things when you're around. I really appreciate that!
Whenever Bugs Bunny interacts with LeBron, he drops the usual jokey quips he'd say to other characters and makes it clear that he's genuinely happy to see his superstar pal again.
Bugs: Still remember how to be looney?
You can guarantee a lot great interactions with ANY partner team up, but arguably the most heartwarming partners goes to Arya Stark and Batman should they work together, especially how both of them will acknowledge they're not that different. Given that both of them had to deal with Death by Origin Story that made them the Heartbroken Badass they are in their respective sources, that says something.
Jake is friendly with nearly anyone who teams with him, but especially with Shaggy, a fellow food lover and a dog's best friend. Sometimes, Jake will even warmly comfort and encourage a nervous Shaggy as a match begins.
Jake: Hey, don't be scared, dude. We got this, no problem.
Reindog fondly reminds both Superman and Shaggy of their own beloved dogs, Krypto and Scooby respectively.
Marvin becomes oddly friendly when teaming with Rick. Between saying he's much smarter than any other Earthlings he's met, offering to give him Ray Gun tips, and even offering to split the Multiverse 60/40 with him, it's clear that he's very excited to hang out with this apathetic human scientist. It's honestly pretty refreshing to see Marvin act so nice around someone.
He even respects her as a Worthy Opponent.