These are the ones I know, but I'm just curious if there're any others that I've missed. Bumblebee: Blitzwing – Bumblebee Prequel Comics Hardtop – 2007 Toy Bios Barricade – 2007 Movie/Game Shadow Striker – Cyberverse Wasp – Animated Arcee: Airachnid – Prime Cartoon Starscream – Prime Cartoon Jhiaxus – IDW Comics Optimus Prime: Megatron – Pretty much everything Ratchet: Blackout – 2007 Toy Bios Lockdown – Animated/Movies Ironhide: Brawl – 2007 Movie Game Bludgeon – Cyber Missions Scorponok – Energon Cartoon
From the Earth Wars game: Sentius Magnus: Sentius Malus Pretty easy when your main gimmick is having a literal Evil Twin.
Well that's a lot less fun. Are we your personal consultancy firm? Ratchet and Megatron's rivalry in the Marvel Comics actually got more focus than Megs Vs Prime. They even got fused into a mess when Ratchet pushed Megatron into a space bridge explosion. See my profile pic. Ratchet went to the 'Savage Land' in the very early 84/85 issues to rescue the Dinobots and bring them back to fight Megatron. Megatron kidnapping Ratchet in Prime and their interactions ARE very reminiscent of Megatron kidnapping Ratchet in late 80s Marvel G1 to do work for him instead of the Autobots. You also missed RID15 Steeljaw who was actually conceived to be Bumblebee's archnemesis and did very good in the role. EDIT: I reckon between Stronger, Faster and the Cybermatter arc, and other interactions, Prime Ratchet definitely counts as having a personally fleshed out rivalry with ol Buckethead MacToothy.
Yeahhh Optimus is REALLY scarce actually. There's The Fallen (RID and ROTF) Scorponok (Marvel G1 until they got along more) Lockdown (AOE) Sentinel Prime (DOTM and Animated, and IDW) Grimlock (Animated, G1 Marvel, AOE, more I'm sure) Galvatron (All over the multiverse, and he is indeed a separate character) Overload (RID15) Scourge (RID01) Starscream (Multiple Occasions) Jhiaxus (G2) Beast Megatron (blew his head right to slag after all, and he was integrated into Primal's frame for the ensuing battle) Shockwave (Multiple Occasions, Marvel G1 and IDW1 stand out to me) Unicron And thats not even scratching the surface.
Cartoon and Toys Dinobots vs Devestator Armada Hot Shot vs Wheeljack G1 Ultramagnus vs Galvatron Primus vs Unicron G1 Overlord vs Ginrai Metroplex vs Trypticon G1 Predacons vs Skylinks Beast Wars Rattrap vs Tarantulas G1 Tracks vs his own reflection Beast Wars Neo Guiledart vs Archadis
Bumblebee's rivals... Wasp Barricade Stinger Lockdown Shatter Steeljaw Shadow Striker Starsceam I know it never happened but I really want to say Bugbite. Ratchet... Megatron Knockout Pharma Lockdown
Soundwave was also listed as his rival on Prime toy bios... I think mostly because they were both mute... even though Soundwave CHOOSE to be mute and actually was capable of talking any time he wanted to. I also kinda see Starscream as a rival... no particular continuity just they both seem to be the most popular characters after Optimus and Megatron of course. Also... Motormaster - G1 Scourge - RID1 Nemesis Prime - Armada* and Prime** *Sideways was basically Nemesis Prime in Armada. **Silas piloted Nemesis Prime in Prime, here he was not a real transformer in that he was not sentient with a spark. (Not including the movie version since that actually was Optimus Prime himself.) Knockout - Prime Mostly just due to them both being the medics of their respective teams.