12 Nov 2010 12 Jan 2011
This achievement is really, really easy. Toward the end of the last level you will need to progress by riding the funicular lift to the next area.
After you provide power to the lift, run back to the lift to hit the button to start the sequence, and the game will checkpoint here. On the left side, as you go up, there will be two outcroppings, the first with four guys and the second with up to five. Make sure you kill all the bad guys in each section (for a total of eight or nine), and after passing the second section the achievement will pop.
You may want to have a couple focus aims ready, because there is one bad guy who always runs for the door. You must get all eight for the achievement. Also make sure you take cover behind the crates after you hit the button. If you mess up, just restart the checkpoint.
Based on the comments below, I found a YouTube video and linked to help. Credit goes to TheGamedump for the video upload.
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