My therory what and who this might be is this gigantic horn looking object cud be unicron who is the planet earth like in transformers prime what are your thoughts on what this is

 

I don't think so with what we've heard Unicron is not likely going to be in this I mean we've been guessing Unicron since the second movie true we have a little evidence to support it but I just don't think so.

I'm guessing that horn is part of the knightship which will serve as Megatron's base.

 

I don't think think it is but crazier things have happened in these movies. I think it's just a random cybertronian ship. It looks like they are going all out with linking earth and cybertron's pasts and this is one of the examples. Probably because it looks like we'll be getting an actual explanation continuity wise of why cybertronians won't leave earth the hell alone haha

 

I think its a ship.
You can also see smaller vessels flying around it.

 

thats my guess to

 

Are we sure this picture is an Earthen desert? I mean, Most likely it is, but it could be somewhere else in the universe.
On topic though ... it does not look like part of the Cybertron, hanging down from the sky -- it could be a different version of the star harvester, shown at thte start of the movie, to help narrate that part of history.

 

Those are birds flying around the horn

 

We dont know that for a fact.

 

I thought it was part of the Knight Ship

 

I think it's primes getaway ship from lockdown, and megatron has borrowed it

 

It's a different design altogether. Besides, that ship that Prime and the others used in AOE, crashed and broke apart. So I don't think it's being fixed.

 

maybe it´s some form of excape pod that separated from the knightship !?

could also be the dragon´s alt mode since some people have pointed out that he has some pieces that resemble the knightship

maybe in his dragon mode he serves as some kind of scout and is seen in the knight era looking for megatron

 

Check the trailer and you'll know.