The sport arcs was the worse for me since it felt boring. How this a science fair turn into a war arc? I didn't pay attention as much. I agree it didn't feel like a proper ending. Just a teaser.
@takashichea: The machine they made for energy was a target but it was the misleading as it was not the real target. The magic guild so to speak that has tons of knowledge was the real target. The guy who used scent magic an persuasion kind of turned over the ones near him. Mostly to look like he had nothing to do with it.
Again if the mechs they had with them were as half as dangerous as they looked things would have been more interesting. Still over all I would argue it was above average. Some shows has small faults an some go big. They went for the big ones it seems.