Re: What villains are left for a 4th film?
^I dont know, I think the 4th movie needs to be its own thing, have a totally seperate villain/s like Thunderwing or Straxus. Have a teaser maybe at the end of TF4 showing Megatron being rebuilt into Galvatron.
THEN build up Unicron through movie 5 and reveal him in movie 6 as the big bad.
2016 movie ratings out of 10:
Revenant-8.5(3)Batman v Superman: DOJ-8