Spoilers ahead for anyone who has not seen the 3rd season of the G1 cartoon, or Transformers: The movie!!!
During the third season of the G1 cartoon series, there was an episode called "Call of the Primitives" which gave Unicron an origin story of sorts. I stated the he was the creation of an alien individual known as Primacron. Unicron turned against his creator, causing him to flee. Later, Primacron created another destructive being called Tornedron. This creature appeared to a type of living energy that could take on different shapes and sizes, as well as drain the life energy of other living things. It also appeared to be impervious to conventional weapons.
For more info:
http://tfwiki.net/wiki/TornedronI'm sure there are many here who remember that episode. It always made me wonder what would happen if Unicron and Tornedron met. Would Unicron offer him a life of servitude, as he did Megatron? Would Tornedron accept, or would the two just fight it out? Something tells me that is what would happen, but who would win?
Anyone who saw Transformers: The Movie knows that standard weapons didn't do squat to Unicron. At best they caused cosmetic damage to him, enough to annoy him perhaps, but nothing came close to stopping him. Hell, they even rammed a spacecraft through his eye. The only thing that could stop him was of course the Autobot Matrix of Leadership, which makes one wonder if it could also stop Tornedron? Rodimus Prime never took it out to attempt to use it, but it was probably because it all happened so fast, and at the time he did not know what they were dealing with.
Unicron told Megatron that the Matrix was "The one thing, the only thing, that can stand in my way". Perhaps that was true, or perhaps that was just Unicron's ego talking.
So what do you think? Do you think Unicron with all of his powers could have somehow neutralized Tornedron, or even bend him to his will? Or do you think Tornedron would have absorbed Unicron's energy, leaving him a lifeless husk?
Personally, I'm going with Unicron. I would bet he would have some way of withstanding Tornedron's attack, but I could be wrong. Maybe the fight would have ended in a draw.