I don't know why, but this one is really giving me trouble. I've currently got 65/70 achievements, I'm missing the 2-all, the 10 million points from a single enemy, two of the Caravan Mode ones, and the lockshot.
How exactly does the lockshot one work? Do I need to be locked on to the same single target for 30 seconds, or just locked on to SOMETHING for 30 seconds? This one seems like it should be really easy, but it is driving me insane. Is there a video demonstration of it anywhere?