- All-Star Cast: The N64 games showcase some of the top American cartoon voice actors from the '90s, such as Jim Cummings, Charlie Adler, Tress MacNeille, Jess Harnell, and Rob Paulsen.
- Creator Backlash: The producer of C2: Judgement Clay was so disappointed with the animation, that he had Tiny (a character from the previous game) put into the game with no changes to his model to show that the previous game's character models were better.
- Executive Meddling: The series was hit VERY hard by this during The Fifth Generation of Console Video Games. 63 1/3 was originally going to be titled "Clayfighter III" and appear on a Vapor Ware console called the M2. However, about a year before the M2 was officially cancelled, Interplay abruptly moved development of the game to the Nintendo 64 and retitled it "Clayfighter 63 1/3".
This caused MANY problems during development: character animation needed to be stripped down due to the N64's cartridge limitationsnote , several of the game's planned fighters needed to be cut, etc. Adding insult to injury, the game was rushed to be released during the 1997 Holiday Season, resulting in an Obvious Beta with numerous glitches and underdeveloped ideas. The Clayfighter 63 1/3 debacle was, in fact, so bad that about six months later Interplay released a rental only update to the game titled "Clayfighter: Sculptor's Cut." To make things even MORE messy, a Playstation game titled "Clayfighter X-Treme" was also in development but scrapped for being behind schedule. These problems, combined with 63 1/3's extremely poor critical and public reception, were what ultimately killed the franchise.
- Vapor Ware: An installment for the Nintendo DS and Wii entitled Clayfighter: Call of Putty. Screenshots suggest it was an Updated Re-release of 63 1/3.
- What Could Have Been:
- Ickybod Clay and a female gorilla called Lucy were planned for C2: Judgement Clay, but were ultimately cut. Ickybod's bio from Clayfighter 63 1/3 even hints at this development, stating that he was "exiled" from that game.
- A homeless vigilante called Hobo Cop was planned for Clayfighter 63 1/3. Nintendo said no due to the alcoholic references.
- Also, some possible moves that were cancelled in 63 1/3 for being so controversial as Hobocop himself, like Lockjaw Pooch peeing the opponent and Zappa Yow Yow Boyz eating alive the enemy.
- A ported/parallel developed version (it's unclear which) of 63 1/3 was planned for the PlayStation entitled Clayfighter Extreme but was canceled.