* ActorAllusion:
** Ditto is not Creator/RobPaulsen's first role as [[WesternAnimation/{{Animaniacs}} a black-and-white wisecracking creature of indeterminate species.]]
** In one episode where Ben and Gwen get sucked into a video game, Grandpa Max (Creator/PaulEiding) tells them to [[VideoGame/MetalGearSolid2 turn the game console off.]] One video on Youtube explicitly noted that, like his role as [[VideoGame/MetalGearSolid Colonel Roy Campbell]], Max carries many, many secrets and often acts as MissionControl.
** Richard [=McGonagle=]'s no stranger to voicing [[WesternAnimation/StarWarsCloneWars four-armed aliens]].
** This is not the first time Creator/RobertPatrick played a [[Film/DieHard2 rogue mercenary member of an elite special forces-esque team]] who pulls a FaceHeelTurn out of {{Greed}}.
** Also, regarding the Japanese dubs...Creator/NoriakiSugiyama voices a dark haired EvilFormerFriend who's has an InferioritySuperiorityComplex towards the main character and pulls a HeelFaceTurn. Are we taking about Kevin, or Sasuke Uchiha?
* GodDoesNotOwnThisWorld: Man of Action Studios created the original ''{{Ben 10}}'' show. It has been repeatedly stated by them and others that they have nothing to do with [[Ben10AlienForce the]] [[Ben10UltimateAlien three]] [[Ben10Omniverse sequels]], as ''Ben 10'' is owned by Cartoon Network and those shows were given entirely different creative teams. Ironically, Cartoon Network has brought Man of Action back on for the ContinuityReboot.
* IKnewIt:
** In the first episode Max corrects Gwen that Ben had turned into an alien instead of a monster, leading fans to think he was involved with aliens sometime in his past, as it turns out he was part of a an intergalactic law-enforcement organization called the "Plumbers".
** Some guessed that Ghostfreak would turn evil when they found out the MonsterOfTheWeek was an Ectonurite in "Ghostfreaked Out", despite some sources saying that it was a completely separate Ectonurite. When the episode aired, the truth became apparent after a nightmare detailing Ghostfreak telling Ben to ''let him out of the watch'', and then subsequently escaping the watch after dealing with Zombozo's unemployed henchmen.
* PlayingAgainstType: Creator/RichardStevenHorvitz as Grey Matter. The little alien is certainly more subdued (and a heck of a lot smarter) than a few of Horvitz's [[WesternAnimation/TheAngryBeavers other]] [[WesternAnimation/InvaderZim well-known]] [[WesternAnimation/TheGrimAdventuresOfBillyAndMandy roles]].
* WordOfGod states that Humans (Homosapians) in the series actually have special powers all their own but it isn't as obvious as other species. They can interbreed with most other species, they are one of only a very select few who can us magic and manipulate mana, and they are the only species who have a form of Adaptability which makes them suited to live in various climates, terrains, and even outer dimensions with little to no effort.
* At the very end of the where the elves try to get Grandpa Max to be Santa, you'll notice that the three children who talk to the old man look familiar. Who are they? Why, none other than Konohamaru, Moegi, and Udon from Naruto!
** And "Super Alien Hero Buddy Adventures" has Sakura Haruno (from Naruto's team, minus the pink hair) near the end in the crowd.
* WhatCouldHaveBeen
** The initial pitch of the show seemed to be inspired by ''ComicBook/DialHForHero''; Ben Tennyson's prototype transformations were more along the lines of '''human''' superheroes, rather than StarfishAliens.
** Ben himself was initially designed with YouthfulFreckles and red hair.
** Gwen was initially written as an unrelated classmate who happened to be Ben's best friend. It is unknown why she became a cousin instead, but the most likely reason was so that it would be easier to figure out an acceptable justification for her to be on a long road trip with Ben. This DevelopmentGag is referenced in the WhatIf episode "Goodbye and Good Riddance", where Ben and Gwen become classmates at the end of the episode in order to better combat villains that might attack their hometown.
** Cannonbolt was originally meant to be in the original set of 10 aliens, but was eventually dropped in favor of Diamondhead.
** "Inferno" was considered as a name for Heatblast. Amusingly, this name was used for the Polish and French dub.
** Benwolf went through [[http://tnperkins.deviantart.com/art/Path-of-Development-Benwolf-79542661 numerous designs]] before being finalized.
** [[http://tnperkins.deviantart.com/art/Path-of-Development-Upchuck-79154482 Several designs were considered for Upchuck]]; two of them ended up re-used for future aliens Spitter and Articguana, and two more became villains in "Ken 10."
** Eyeguy was initially rejected due to being seen as too creepy; only when ''Secret of the Omnitrix'' did the writers decide to use him in an alternate scene.