Help with Best Defense Achievement

[Pick]

Key points are to abandon the lower ground, you just need it for the normal achievement. Secondly never ever stop building, pump constantly and if you get to 200/200 you waited to long. Also lure the Zerg away from the crawlers, they will slaughter your Marines.

Agree with the guys who say abandon the low ground early. Retreat to top level and it is much easier to hold a single choke while you build up a huge M&M ball of doom. Then you can leave a smaller amount of units behind to defend while you hit the hatcheries.

And don't forget to upgrade. +1 attack and defense helps a lot when you push.

[Maisto]

http://www.youtube.com/watch?v=drzcbbAicpM

This is exactly how i did it, was super easy and fast.