Back to the Future

- G1 Megatron learned to create that time travel device used in War Dawn somehow! Or maybe Doc learned it from him...

Star Wars

- No one in the SW universe knows where the technology for hyperspace travel comes from. Or the tech for sentient droids...

Master of Universe

- Two words: HORDE PRIME.

Teenage Mutant Ninja Turtles

- Transformers aren't the only species that hops dimensions. Imagine if the Technodrome... transformed!

 

Two things I'd like to come back could work:

Battle Beasts - Not really random as it is already connected in Japanese fiction., make beast-formers that can also interact with a new BB line.

Centurions - Transformers with add on accessories for different missions, maybe even change vehicle types.

 

Only if they all get Transtector bodies and/or become SoundMasters or something equally as ridiculous as befits a 1980's crossover.

Other potentially fun crossover ideas:

* Fallout - Liberty Prime vs. Optimus Prime, and awesome retro-future altmodes.
* MotorCity - Dystopian Detroit + Supercars can only get better if they turn into giant robots, too.
* Avatar LA/LoK - Steampunk, mysticism and giant arcane sentient mecha, for those that like the spiritual side of Transformers.

 

Gobots