What made the machines?
A movie for when you don't want to think about anything in the movie, simply put some mindless fun. The visuals are what you would expect from Hollywood, along with the action scenes, there is also some humour thrown in. What all this means is don't expect much from the plot, don't analyse the story, just sit back and enjoy the good guys wining.
The Allspark is of course on Earth, so the humans are now in the fight too. The question is who will find the Allspark first and possibly put an end to the war.