Gears of War: Judgment

For this achievement I did this solo and used a second controller as an AFK player on the COG side, and I took the locust side. Having one less COG enemy to worry about makes thing easier. Put the difficulty on casual. I played on the map Ward.
I first took the ticker and chewed through the first couple of fences, then took the grenadier. By the time I got past the first section I had enough money for a mauler and used that the rest of the way. You should get this pretty easily with this method.
Achievement will pop immediately after you destroy the generator if it's under 8 minutes.

with 2 players on Terminal,go left side the whole way(only 8 fences),1 Ticker the other Grenadier,the grenadier kills the cog protecting the Ticker while they chew done the fences & bombs the first hole then the mauler should be in play.After the second hole the Grenadier player should also have a Mauler(if not no biggie) in play,go smash them suckers.Have done this method for 3 players now all times under 5mins with the quickest being 4min 15 secs to destroy generator.