Big-Lipped Alligator Moment: Sergeant Sensible; either you're not a Kids Next Door fan and you don't know who he is, or you are a Kids Next Door fan and you don't know why he's with the Candy Pirates.
Mojo's first fight is arguably one of the easiest in story mode as you don't need to damage Mojo, just the core.
Crack Pairing: Non-shipping example. This trope is used as a gameplay mechanic via Synergy Assists, where each character gets a special attack from activating one particular assist character. The crack part comes from the two characters being from two different shows and having no relation to each other. One of the announcer's lines when a Synergy Assist is activated refers to this effect.
Cult Classic: While critical reviews and sales were nothing spectacular, the game still has love among the Cartoon Network fanbase due to the usage of crossovers.
The "It's Over 9000!" achievement may seem random, but then you remember that Dragon Ball is a mainstay on the Toonami block, where most saw the original scene for the first time.
Game-Breaker: Kevin 11 in Story Mode, due to having powerful, spammable attacks, and if you grind, his Punch Time Explosion pretty much ensures that any enemy onscreen will not be onscreen anymore.
At the end of Bubbles' story mode, she loses Octi, leaving her alone and scared. Cue none other than Captain K'nuckles showing up to keep her company! Given further context in K'nuckles' own story mode, as he actually took time out of his search for Candied Island to comfort her until Buttercup found her again.
Bubbles hugs Eduardo in their Synergy attack. Aww.
Aku is despised for his quick and far reaching laser attacks that he can spam relentlessly, creating a wall of lasers which very few characters have an answer to.
Blossom is considered the best of the three Powerpuff Girls for one thing; her ice-breath attack, which is capable of infinitely chaining into itself, has a huge hitbox and can be spammed relentlessly. Combine this with her incredible speed and combo potential, her multiple jumps allowing her to recover from anywhere on the stage and her small size making her unbelievably difficult to hit, and you've got a recipe for a Lightning Bruiser who's considered one of, if not the best characters in the game.
Cartoon Network at one point had Sweepstakes for getting a copy of Super Smash Bros., called the "Smash Hit Giveaway" (Can be seen here). Several years later, they create this game.
The game was released on both the Wii and 3DS. A few years later, Nintendo would do the same thing with the fourth Smash Bros. game, though for the Wii U instead of the Wii.
A lot of elements of this game seem to predict elements of Super Smash Bros. for Nintendo 3DS and Wii U. Mac & Bloo's neutral special is the same as Ryu's, the 2nd Foster's stage is reminiscent of the Tomodachi Life stage, both Captain Planet and Blossom's neutral special are similar to Kirby's Ice Breath custom move, etc...
In this game, there's a meter on the bottom of your character's portrait and stock count that you have to fill to use your Limit Break. Super Smash Bros. Ultimate has a feature that includes a Final Smash meter.
The story mode begins with an evil creature eradicating most of the Cartoon Network characters and controlling dark Empty Shells of themselves with the only survivor being Ben 10. The World of Light mode in Super Smash Bros. Ultimate starts off with Kirby being the only survivor after a evil deity kills off every playable character and creates shadowy Empty Shells of them. Humorously, Ben's middle name is Kirby.
Just Here for Godzilla: While the actual mechanics are heavily disputed from a gameplay standpoint, the sheer awesomeness of seeing all these beloved cartoon characters duking it out make it all worthwhile anyway.
Low-Tier Letdown: Flapjack is considered low tier due to his weak attacks and lack of range, while Young Ben suffers from incredibly laggy attacks that don't deal enough damage to compensate for how slow they are.
Obvious Beta: There's a ton of lazy development quirks that almost make the game unplayable. Unresponsive controls, an unfinished battle system, and an unintuitive control scheme that even the veteran Smash player finds hard to get used to. There's also a quite infamous bug that freezes the game during one of the final levels. Granted, there are ways to bypass this bug (many people did it just by sheer luck) but it's still a problem that makes the game a textbook example of Obvious Beta.
Questionable Casting: Most of the playable cast aren't voiced by their original actors, and the replacements are extremely noticeable. Nolan North as Father, Captain K'nuckles, Mojo Jojo and Hoss Delgado is the worst offender, as his distinctive voice doesn't sound anything like any of his characters' original actors.
Sequel Displacement: Due to the Updated Re-release on consoles coming less than a year after the original 3DS release, most people don't even know the 3DS version exists.
They Copied It, So It Sucks!: The game received a lot of flak for it being the same as Super Smash Bros. The game included the following from Smash: the damage percentage, the lives, the charge up attacks, the assist item, and the story mode that involves an evil overlord that goes around causing chaos and destruction and gathers the villains to destroy the heroes with the only exception being the online content.
Captain Planet, a character that wasn't relevant in decades and doesn't even belong to Cartoon Network, is in this game, unlockable via a Big Damn Heroes moment right at the end of the story mode.
No one expected Toiletnator to join in the XL port, since he was little more than a comic relief villain in his home series.
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