While both Creator/PeterCullen and Creator/FrankWelker have portrayed Optimus Prime and Megatron in other productions including video games, this is the first time the two of them have been able to work together portraying their iconic characters in a television series since ''WesternAnimation/TheTransformers''. Both have stated how delighted they were to work together again and how fond they were of each other.

* ActingForTwo: Greg Sepelak voices both Rumble and Frenzy in the ''Unreliable Narratives'' script reading.
* ActorAllusion:
** Creator/JoshKeaton once again plays [[WesternAnimation/TheSpectacularSpiderMan a snarky teenager who's often the target of bullies]]. He's also had previous experience with spiders, except this time he's on the opposite end of the webs and in "Darkness Rising, Part 4" talks about being taught to be responsible.
** Ratchet becomes a manic MadScientist over the kids' science fair projects. It's as funny as it sounds, particularly when Jack's machine starts spasming like a severed limb.
*** Later on, he tests synthetic energon on himself that leaves him with unexpected results.
*** Oh, and the synthetic energon looks suspiciously like [[Film/ReAnimator another glowing, green liquid]] that Creator/JeffreyCombs has worked with in the past.
*** And in "Scattered", he hides out in [[WesternAnimation/JusticeLeague everyone's trash]].
** [[spoiler: Creator/WillFriedle plays [[WesternAnimation/BatmanTheBraveAndTheBold a young, brash, brightly-colored hero with an insect theme]]. [[WesternAnimation/BatmanBeyond He also inherits his role (as leader) from an older hero who trained him]]. He's even colored mostly black when it happens.]]
** This wouldn't be the first time Creator/NolanNorth's voiced [[WesternAnimation/YoungJustice a young hero who idolizes an older, red and blue-clad hero]].
** Ultra Magnus is voiced by Creator/MichaelIronside. [[spoiler:[[{{Fingore}} Yeah, he's not going to keep that hand.]]]]
** Creator/ClancyBrown plays the human super villain Silas, who bedevils Optimus Prime. By coincidence or design, this is the second time Clancy has found himself playing a supervillain who is an antagonist to a [[WesternAnimation/SupermanTheAnimatedSeries benevolent super-powered alien primarily clad in the colors red and blue]]. This goes UpToEleven when he goes all BaldOfEvil in "The Human Factor."
** In the Japanese version, Arcee and Jack are played by Creator/ShizukaIto and Creator/JunFukuyama respectively. They reprise their roles from the RomanticComedy HaremAnime ''VisualNovel/ToHeart2'' in that they once again play a couple with a Big-Sister and Little-Brother relationship.
** Similarly, SteveBlum in the original version once again plays Shin from ''Manga/FistOfTheNorthStar'', in that Starscream is a sadistic warlord who takes pleasure in shoving his hand through the rib-cages of helpless prisoners.
** Cliffjumper's vehicle mode has bull's horns on the front of the hood. One of the nicknames his original voice actor, Wrestling/DwayneJohnson, has when performing as The Rock is "the Brahma Bull".
* BreakthroughHit: Stands with ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' as one of the shows responsible for Creator/TheHub's success.
* DawsonCasting: Andy Pessoa is a teenage actor playing 12-year-old Raf, though they are already running into problems with keeping his childlike voice and his voice has clearly deepened as of the season 2 premiere.
* FanNickname:
** Screamernaut and Iron Screamer after Starscream [[spoiler:gets the Apex Armor and becomes a nigh-unstoppable war machine]].
** Silasdown for [[spoiler:Silas' fusion with Breakdown's corpse]].
** Yanderachnid for Japanese!Airachnid.
** "Galvatron" for [[spoiler:Megatron after Unicron brings him BackFromTheDead and then [[DemonicPossession takes over his body]], [[BodyHorror radically altering it]]]]. Contrary to fan expectations, the name was never actually used in the show, [[spoiler: not to mention ''The Covenant Of Primus'', much like [[ComicBook/TheTransformersIDW IDW's continuity]], has Galvatron as a separate entity from Megatron.]]
** Soundwave is "[[Franchise/TheSlenderManMythos Slendercon]]."
** Given his habit of stealing artifacts off the Decepticon Warship, Smokescreen is sometimes referred to as "[[SmokeyAndTheBandit Smokey the Bandit]]."
** [[spoiler:"[[WesternAnimation/BatmanBeyond Bumblebeeyond]]" or "[[Creator/WillFriedle Friedlebee]]"]] for [[spoiler:the newly voiced Bumblebee.]]
* FlipFlopOfGod: The western release makes Rumble blue, while the Japanese release makes him red. And thus "FIRRIB"[=/=]"RIRFIB" is preserved for a new generation.
** The whole thing is lampshaded in the 2013 script reading, when the transfer to new bodies results in the two of them being placed in the ones with the wrong colors. By the end of the whole mess, not even Rumble or Frenzy are sure which of them is which.
-->'''"Frenzy"/"Rumble"''': This is the kind of thing that can keep people arguing for decacycles!
* HeyItsThatSound:
** Both Skyquake's stasis pod and the Energon Harvester activate with the sound of [[Series/StargateSG1 Stargate's]] zat gun - as do the stun beams fired by the ''Nemesis''.
** Airachnid's web-shooters make the same sound that SpiderMan's do in ''WesternAnimation/TheSpectacularSpiderMan''.
** At least three sounds seem to have been lifted directly from WesternAnimation/RoughnecksStarshipTroopersChronicles: the alarm in the Autobots' base is the same as that on the Valley Forge, Starscream's missiles swoosh like Javelin missiles and when Ratchet's medical probe is brought to unlife by Dark Energon it screams like a warrior Bug.
* IKnewIt: Many had guessed [[spoiler: Unicron was either Earth, or somehow connected to it]], due to the fact [[spoiler: Dark Energon ''erupted from a volcano'']].
** Given both ''Prime'' and ''TransformersWarForCybertron'' are set in the Franchise/TransformersAlignedUniverse, [[spoiler: Ratchet's recap of ''[=WfC=]'' confirms that the being credited as "Core" in the game is indeed Primus.]]
* InMemoriam:
** [[Recap/TransformersPrimeS1E20Partners "Partners"]] was dedicated to the memory of Captain H.L. "Larry" Cullen, the brother of Creator/PeterCullen who died four months before the episode aired. While Captain Cullen was never personally involved with the ''Transformers'' franchise, Peter has said he looked to mirror Larry in his performance (specifically the ability to be powerful and commanding but gentle at the same time). In short, the inspiration for Optimus Prime passed away.
** [[Recap/TransformersPrimeS3E12Synthesis "Synthesis"]] was dedicated to the memory of Armen Mirzaian, a storyboard artist for the show who was killed in a car accident about a month before the third season premiered.
* LyingCreator: [[spoiler: Originally, it was stated Ironhide was going to be on the show, but so similar to ''[[WesternAnimation/TransformersAnimated Animated]]'' Bulkhead that they just opted to do Bulkhead instead. However, so the Season 1 set, the reason given was because of Ironhide's death in ''[[Film/TransformersDarkOfTheMoon Dark of the Moon]]'', hinting the reason given earlier was a lie to prevent spoilers.]]
* NamesTheSame:
** Miko Nakadai is bored with life and so [[TheLoad constantly gets in the Autobots' way]]. [[Series/BakuryuuSentaiAbaranger Mikoto Nakadai]] is bored with life and so [[SixthRangerTraitor constantly gets in the Abarangers' way]]... by beating the crap out of them. It doesn't help that both characters are Japanese, and both shows deal with [[TransformingMecha giant transforming robots]] that can talk.
** Dive Bomb shares a name with the [=G1=] Predacon, but his character concept and colors have very little connection to the original.
* NoExportForYou:
** So far, at least a good third of the tie-in toyline, including the entire ''First Edition'' series, will not be released in the United States... particularly galling since this is where Hasbro's main corporate offices ''are actually located'' and the aforementioned ''First Edition'' series were released in Canada.
** So are the Arms Micron versions of the toyline... and the separate Arms Microns. They're Asia-only.
** And therefore, the same goes for the "Arms Micron Theater" shorts.
** The third season of the show, ''Beast Hunters'', has fallen into this for Japanese audiences. Instead, it's been replaced with a new OVA series entitled ''Anime/TransformersGO!'', which takes place sometime after the missing third season itself. Same with the ''Predacons Rising'' TV movie.
** Ironhide, Swerve, Leo Prime, Frenzy, and Wildrider are currently exclusive to Japan. Conversely, Thundertron is exclusive to the States.
* TheOtherDarrin: Given it's set in the same universe as ''VideoGame/TransformersWarForCybertron'', Optimus Prime is the only character who appears in both ''[=WfC=]'' and ''Prime'' that doesn't undergo this, as Creator/PeterCullen voiced Optimus in both. The humans, Bulkhead, Knock Out, Skyquake, Airachnid, Makeshift, Wheeljack, Tailgate, Dreadwing, and Smokescreen didn't appear in the game, and the portrayals of Bumblebee and Soundwave haven't required voice actors [[spoiler: until season three.]]
** FredTatasciore is replaced with Creator/FrankWelker reprising his iconic role as Megatron from ''G1'' and Creator/JeffreyCombs as Ratchet.
*** [[spoiler:When the Nemesis is reanimated (it was technically Trypticon)]] Creator/KevinMichaelRichardson replaces Fred as well.
*** Fred recently found himself on the other end of this trope in [[LicensedGame the game]], filling in for Creator/TonyTodd as Dreadwing.
** [[spoiler: In reprising his other iconic role from G1 as Soundwave, Frank Welker is also this to Isaac C. Singleton Jr.]]
** Creator/SumaleeMontano replaces Creator/KariWahlgren as Arcee.
** Creator/SteveBlum replaces Creator/SamRiegel as Starscream, though Steve is also an interesting case, as he voiced Cliffjumper and Shockwave in ''[=WfC=]'' and the latter again in ''VideoGame/TransformersFallOfCybertron'', yet Wrestling/DwayneJohnson voiced Cliffjumper in "Darkness Rising, Part 1'', then he himself was replaced by Billy Brown in "Out of the Past" while Creator/DavidSobolov replaces Blum as Shockwave in the same episode.
** Creator/AdamBaldwin takes over from Creator/CrispinFreeman as Breakdown.
** Creator/MichaelIronside replaces Creator/JamiesonPrice as Ultra Magnus.
** [[spoiler: Creator/WillFriedle replaces Creator/JohnnyYongBosch as Bumblebee.]]
** In the Hungarian dub, Jack, Airachnid, and Alpha Trion get new voices in season 3, with Ratchet joining them halfway through the season. The first two seasons were otherwise consistent (surprising for a Creator/CartoonNetwork dub), only Skyquake's voice changed for a brief flashback.
** The German dub recast Optimus' voice actor after the first season (Reiner Schöne -> Klaus-Dieter Klebsch).
* PlayingAgainstType:
** GinaTorres as Airachnid.
** Creator/DaranNorris as Knock Out.
** Zig-zagged with MichaelIronside as Ultra Magnus. Ironside is well known for playing contemptuous military commanders in live action and his voice acting roles tend to be along the lines of villains or [[AntiHero morally dubious]] heroes. Thus playing a very straight laced military officer is unusual.
* RealitySubtext: "Decepticons! [[Creator/FrankWelker I]] have [[WesternAnimation/TheTransformers returned!]]"
* RecycledScript: In "Armada" [[spoiler: Starscream uses a bunch of protoforms to create a gang of clones to assassinate Megatron. [[WesternAnimation/TransformersAnimated Sound familiar?]] They even use the same number of clones. On the other hand, ''this'' Starscream is aware that they share his traitorous nature]].
* RelationshipVoiceActor:
** In "The Human Factor", the Creator/KevinMichaelRichardson-voiced Bulkhead fights the Creator/ClancyBrown-voiced [[spoiler:Breakdown!]]Silas. [[WesternAnimation/ThunderCats2011 We've seen]] [[WesternAnimation/GreenLanternTheAnimatedSeries this before]].
*** Relating to them, [[spoiler: [[Creator/WillFriedle Bumblebee]] is Lion-O and Ragnar]].
** A good bit of the cast is basically a mini ''WesternAnimation/TheSpectacularSpiderMan'' reunion: [[Creator/JoshKeaton Jack]] is Spider-Man, [[Creator/SteveBlum Starscream]] is Green Goblin and Chameleon, [[Creator/KevinMichaelRichardson Bulkhead]] is Tombstone, [[Creator/ClancyBrown Silas]] is George Stacy and Rhino, [[Creator/JohnDiMaggio Vogel]] is Sandman and Hammerhead, and [[Creator/DaranNorris Knock Out]] is J. Jonah Jameson.
** For the ''WesternAnimation/WolverineAndTheXMen'' fandom: [[Creator/SteveBlum Starscream]] is Wolverine, [[Creator/KevinMichaelRichardson Bulkhead]] is Bishop and Shadow King, [[Creator/NolanNorth Smokescreen]] is Cyclops and Pyro, [[Creator/ClancyBrown Silas]] is Mister Sinister, and [[Creator/MichaelIronside Ultra Magnus]] is Colonel Moss.
** [[Creator/JoshKeaton Jack]], [[Creator/NolanNorth Smokescreen]], and [[Creator/GinaTorres Airachnid]] are [[WesternAnimation/JusticeLeagueCrisisOnTwoEarths the Flash, Green Lantern (Hal Jordan), and Superwoman]].
** For ''Anime/CowboyBebop'' fans: [[Creator/SteveBlum Starscream]] is Spike Spiegel and [[Creator/DaranNorris Knock Out]] is both Cowboy Andy and Vincent Volaju.
** For ''WesternAnimation/JusticeLeague'' fans: [[Creator/JeffreyCombs Ratchet]] is the Question, [[MichaelIronside Ultra Magnus]] is Darkseid, [[Creator/GinaTorres Airachnid]] is Vixen, [[Creator/ClancyBrown Silas]] is Lex Luthor, [[Creator/AdamBaldwin Breakdown]] is Jonah Hex and Hal Jordan, [[Creator/RichardGreen Skyquake]] is Orm, and [[spoiler:[[Creator/WillFriedle Bumblebee]] is [[WesternAnimation/BatmanBeyond Terry McGinnis]] and Kyle Rayner]].
** [[Creator/AdamBaldwin Breakdown]] and [[Creator/GinaTorres Airachnid]] are [[Series/{{Firefly}} Jayne Cobb and Zoe Washburne]].
* SequelFirst: A strange toy-based variation. Kup's mold was obviously intended to be Ironhide from the get go, but he only got released in the US as Kup. Kup's toy even hit shelves in America ''before'' Ironhide's toy did in the Japanese line.
* ShortRunInPeru: Canada aired episodes 21 to 23 several weeks before TheHub did, but then stopped until the two stations were roughly in sync in terms of episodes. Singapore, however, aired the three-part season finale several days before North America did.
** It's happened again as of season three, with the first three episodes airing in Singapore (back to back) a week before the first aired on TheHub (on the standard weekly schedule).
** And now Predacons Rising has been leaked a full three weeks before the supposed air date on Internet Streaming Sites.
* TalkingToHimself: With the Vehicon mooks (and later the Insecticons) all being voiced by Creator/SteveBlum, JoshKeaton, Creator/KevinMichaelRichardson, DaranNorris, and Creator/FrankWelker, this is more or less inevitable. Happens in a literal and somewhat humorous sense to [[spoiler:Starscream when he clones himself]].
* TechnologyMarchesOn: For the Transformers as well as for us. They have portable teleportation technology in place of travelling in spaceships, which have been turned into floating living space. On the other hand, dealing with their non-sentient programs isn't tough because it is more complex than humans, as it is completely different in its encoding and interface.
** ''Our'' technology has marched on to the point that human parts can serve as a cheap fix for Transformers technology. Miko also takes a lot of photos on her cell-phone.
* TroubledProduction. [[http://sunnybutte.tumblr.com/post/131367083128/that-explains-a-lot-of-the-mess-that-was as seen]][[http://sunnybutte.tumblr.com/post/131368170623/and-if-you-were-wondering-why-beast-hunters-was here]], the show went through many problems, mostly because of miscommunication with the other branches of the [[TransformersAlignedUniverse Aligned continuity]] and a late change in director [[ExecutiveMeddling with a different idea for the third season]].
* WhatCouldHaveBeen: Bulkhead was originally planned to be Ironhide, but the creators realized that they were essentially creating a new version of ''[[WesternAnimation/TransformersAnimated Animated]]'' Bulkhead, so they put him in the show instead. [[spoiler: However, the featurette of the Season 1 set states that Ironhide's death in ''[[Film/TransformersDarkOfTheMoon Dark of the Moon]]'' was what made the crew replace him with Bulkhead.]]
** According to a featurette of the Season 1 set, [[WesternAnimation/TransformersAnimated Lugnut]] was considered to be join the Decepticon ranks, but was ruled out because the makers felt they had too many aircraft on the 'Con's side and he was replaced with Breakdown.
** Smokescreen was going to be the sixth Autobot at the beginning of the show and he would then get killed by Megatron during the season finale. He was replaced by Cliffjumper and his death was moved to the first episode.
** Part of the reason Season 2 has so many storylines is that the writers realized that standalone episodes would be hard to maintain due to the very abundant continuity, so they rushed through the storyline ideas that they had. It makes one wonder what could have happened had they gone through the three years as planned.
** Seaspray was going to appear in season 3, having survived his run-in with Dreadwing. He would have had a personality similar to Quint from ''Film/{{Jaws}}''.
** Grimlock was also planned to appear in the series. It's likely, had he made an appearance in the series, that he would have borrowed from his ''Fall of Cybertron'' design or been redesigned. The Dinobots collectively are actually referenced by Bulkhead and Miko in ''Project Predacon'', so take that as you will.
** Creator/MichaelBell, who voiced many characters including Prowl, Sideswipe, and Swoop, auditioned for Ratchet and Fowler.
** Skyrazor was originally planned to be "Stormrazor".
** The ''Beast Hunters'' guidebook originally identified Vertebreak as "Scourge", and showed him with a remolded beast-mode head. Ultimately, this was dropped, and when Hasbro released said guide book on their facebook page, the name was replaced with Vertebreak's and the artwork reflected his status as a redeco of Lazerback.
** The whole ''Beast Hunters'' line was imposed at the last minute (see TroubledProduction above), forcing the team to scrap their original plans for season 3 ([[http://sunnybutte.tumblr.com/post/131384199723/hey-all-getting-a-lot-of-questions-about-those apparently involving Maximals and Predacons and a "wild-west"-style exploration of the reborn Cybertron]]).
** Fowler's Unit:E was supposed to start a MassiveMultiplayerCrossover between many Hasbro franchises, most of them obscure [[labelnote: For example]]''WesternAnimation/{{MASK}}'', ''Franchise/{{Micronauts}}'', ''WesternAnimation/{{Centurions}}'', ''[[WesternAnimation/{{Inhumanoids}} Primor]][[AdaptationNameChange dia]]'', ''WesternAnimation/{{Jem}}'', ''WesternAnimation/{{GIJoe}}'', ''Stretch Armstrong'', ''TabletopGame/{{CandyLand}}''...[[/labelnote]], as seen in [[https://scans-daily.dreamwidth.org/3362163.html the comic that came out at NYCC 2011]]. (Creator/IDWPublishing has recently announced the launch of their own SharedUniverse called ''[[ComicBook/Revolution2016 Revolution]]'', using their ''Transformers'' and ''G.I. Joe'' titles as the foundation.)
** The reason the toyline included the character Thundertron was because he was supposed to be in season 3, until the storyline was altered.
** Unicron was going to enlist the help of Airachnid and her Insecticons during ''Predacons Rising'', but they were cut out in the final film.
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