Collection: Nickelodeon

In December 2023, information spread about Warner Bros. Discovery, which owns Cartoon Network among other major animation brands, potentially merging with Paramount Global, which owns CN's long-standing TV animation rival, Nickelodeon among other animation IPs. Although this deal would not come to fruition at the time, Nickelodeon All-Star Brawl game designer Thaddeus Crews commented that he would take the chance to work on a Cartoon Network vs. Nickelodeon fighting game "in a goddamn heartbeat".

When Smite launched its Nickelodeon crossover event, multiple characters were not voiced by their original voice actors.

• Invader Zim was voiced by Andrew Russell instead of Richard Horvitz
• Rocko was voiced by Matt Cowlrick instead of Carlos Alazraqui
• Jenny was voiced by Jenny Yokobori instead of Janice Kawaye
• Danny Phantom was voiced by Sean Chiplock instead of David Kaufman
• Powdered Toast Man was voiced by Michael Berger instead of David Kaye, his current voice actor and replacement for the now-deceased Gary Owens.

Zim's original voice actor Richard Steven Horvitz claimed that he was not allowed to reprise the role of Zim due to Hi-Rez Studios refusing to work with union actors, and that he felt insulted by the temporary recast. For Jenny, Rocko, and Zim, this game marked the first time they had been portrayed in English by someone other than their original actor.

Many Nickelodeon fans noticed a significant omission of characters from the series The Fairly OddParents in Nickelodeon crossovers starting in 2008's SpongeBob SquarePants featuring Nicktoons: Globs of Doom, which was the final installment in the Nicktoons Unite! series where Fairly OddParents protagonist Timmy Turner had previously been part of the main ensemble cast. The reasoning for this is believed to be due to Nelvana, a Canadian distributor of children's content, holding the international licensing rights and copyright for the first 5 seasons of the show outside of the US, having used this to syndicate the cartoon on the rivaling Disney Channel.

Timmy Turner did later appear in the 2022 Apple Arcade game Nickelodeon Extreme Tennis. In response to a tweet speculating that this could lead to Fairly OddParents content appearing in Nickelodeon All-Star Brawl, the community manager for the latter game Thaddeus Crews posted a "heads-in-the-clouds" emoji. A playtester for Nickelodeon All-Star Brawl 2 alleged that the legal issues with The Fairly OddParents are so complicated and strung-out that a former Nickelodeon or Nelvana employee was gifted the copyright to Timmy Turner's pink hat design as a farewell gift.